# 350 Cylinder compression



## KowalskiCW (Jul 11, 2016)

So I did a little research on here to see what a normal cylinder compression is and seems 150 is key. I checked my compression this weekend while the engine was cold one spark plug at a time. I got 100-110 no higher no lower. I've been noticing quite a bit of smoke at start up lately that eventually goes away, so that's what prompted the check. Also the fact that I have a open diff and can't do a one wheel burnout to save my life haha. 115k on the original motor.
Now I read that you are supposed to do this test with the engine warm, all plugs out and carb open. Did I really get that far off of a reading or is this still indication of a worn out engine? I don't seem to be going thru oil but I've only had it for the summer and haven't had to add oil yet on the initial oil change I did.
I just can't believe a 350 with a cam and 4 barrel carb can't burn one wheel...not even a brake stand!
Thoughts?


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## KowalskiCW (Jul 11, 2016)

I just did more searching and realized I did the compression test all wrong. I'll warm the engine, take out all the plugs(hopefuly not burn myself!) and hold the carb open and try again. I'll report back.
Still don't know why this car can't do a damn burnout! 265hp 335ft lbs should be able to....I digress.


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## bigD (Jul 21, 2016)

That's why most people don't like the 350. And most have low compression.

But, a 350 can be built to make some decent power. The strongest 350's were the '68 & '69 350HO engines. They had over 10:1 compression. And the '69 model even had #48 big valve heads. I had one of these, with a bigger cam, that made 434hp on the dyno. It ran mid 12's in a '69 Tempest. :smile3:

And, about the burnout: you probably have some highway gears, like maybe 2.56, 2.73, or 3.08. You'd probably need a 455 to burn rubber with those high speed gears. For any kind of good acceleration, with a low compression 350, you'd need 3.55 gears. 3.73 would be better. 

Or, you can go with a stall converter that will flash to around 2800rpm when you nail it. That might break the right rear loose. :grin2:


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## REDMAN (Feb 18, 2015)

I to have a 69 custom s with bone stock 350 motor all original with little over 111,000 on the clock. I have no problem getting a burnout when brake torqueing but not much off the line without brakes held down. Im not sure what gears I have since I just bought it couple months ago but it really gets up and goes for a stock motor. I am gonna install a shift kit next week if my buddies tranny shop can fit me in. This winter I am pulling the motor to replace the rear main seal which is leaking bad and wanting to install a ram air cam like in the 69 350 ho possibly and ram air manifolds. Not sure if Im gonna go with the # 48 heads. Currently have #47 stock heads. Havnt had much time on researching that. Its no matching motor so want to keep the drivetrain in it though a 400 would be nice!


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## 1968gto421 (Mar 28, 2014)

My advice would be to avoid the Ram Air cam and go with something like the Lunati Voodoo line. These cams were designed by Harold Brookshire (of Lunati Ultradyne, and Bullet Cams fame). He designed the Voodoo's with closing ramps like GM used, better for your valves and valve seats. In contrast Comp's XE's tend to bounce off the valve seats as they close too fast. Jim Hand, very well known Pontiac performance man for decades (and still racing) uses a Ram Air cam in his 455 LeMans and still does things to bolster low end torque for his big 455 since the Ram Air cam is sadly lacking in low end torque. (From Pontiac Jim---- Building a Strong Street Machine ? Part 5: Pontiac Camshafts | Dallas Area Pontiac Association ) 

To get more low end torque with a cam change try one of these two Voodoo's. Besides torque to fry your tire, they also increase cylinder pressure in low compression engines for more power. Just be careful to evaluate for detonation.
Voodoo Hydraulic Flat Tappet Cam - Pontiac V8 256/262 - Lunati Power
Voodoo Hydraulic Flat Tappet Cam - Pontiac V8 262/268 - Lunati Power

BigD's advice was very good, do consider it. If you do some mods to increase torque, you might look into the stronger 8.5" GM rear end with the gears recommended.

Rather than swapping engines, here is an article to give you an idea how strong a Pontiac 350 can become.

Small-Bore Pontiac Performance Engine Build - Revenge Of The 350 - Hot Rod Network

Hope this is of some help!:smile3:


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## PontiacJim (Dec 29, 2012)

Put a set of 3.90's or 4.33's out back and you should be able to fry tires. No top end however, and your engine won't like highway driving. The 2 series gears or the 3 series ratio's under 3.55's will need some good torque/horsepower to spin tires with an automatic. With a 3/4-speed manual trans you can do it because you can rev the engine, dump the clutch, shock the tires, and spin em'. Unless you want to put your automatic in neutral, rev it way up, and drop it into drive, you may not spin your tires. But this is not my recommendation and you might just drop the tranny.

The 350CI in my book seems to be under rated because everything centers around the more available 400CI and its stroker abilities. I had a '67 Firebird with 350CI 3-speed manual trans that had no problem laying down long strips of rubber with its one-legger rear end and the old 14" 78 series tires. I had an aftermarket tach in it and I'd spin it 6,000 RPM's with no problems. 

I'd like to build a hi-revving Pontiac 350CI just to try it, 6800-7200 RPM's, 475HP/410 ft lbs. Not sure how I would go with trans/rear gears.

My basic build (which could change with better research) off the top of my head would be:

350 block .030" over
Forged pistons 10:1 ratio

4-bolt splayed main caps fitted

forged crank with BB 2.20 rod journals

80 PSI oil pump and big pan

BB 6.7 forged H-beam rods to give a rod/stroke ratio of 1.79 for high revs.

350 CI 1.94/1.66 Iron heads: 
1.stock intake port flow @ 190-210 just cleaned up, no port larger RA IV gasket matching, just stock gasket matching to equalize.
2. fitted w/screw-in BB 7/16" studs & Pontiac guide plates. Pushrod holes elongated for large lift cam.
3. 2.02" valves on the intake. I think I would leave the 1.66" exhaust to keep exhaust gas velocity up.
4. bronze valve guides & teflon seals
5. 3-angle valve job and some port blending and "boat-tail" the intake guides in the bowl.
6. matching valve springs/retainers
7. 1.5 ratio roller rockers to take advantage of the slower opening rate vs 1.65's for a little more improved bottom end performance.

Solid Cam, 112 LSA, 109 ICL, 295 duration -.500" Int, 300 duration -.520" exhaust. Intake closes at 76 ABDC.

Torker single plane intake
780 CFM Holly

1 5/8" headers, duel 2.50" pipes with X-over, low restriction mufflers.

Electronic Dist. & MSD 

:thumbsup:


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## REDMAN (Feb 18, 2015)

Im gonna check my gears but pretty sure they are stock highway gears. I will prob take the advise and run 3:55 gears so it will still turn good rpms at highway speeds. Looking into the cams suggested. Dont want to spend money doing head work when Im pretty happy with the weekend cruiser just looking for a few extra horses etc. I have a edelbrock performer intake with new edelbrock 650 avs that we just tuned but still gotta tweek the vacum secondaries. Slight hesitation when kicked in. Just installed new 2 1/2 pypes exhaust but havnt installed the tailpipes as of yet. Did make a difference from the 2 1/4 exhaust and sounds great with the new pypes headpipes and streetpro mufflers. I have read many threads from aly and bear in regards to the 455 swap and would like to do that in the future and still keep the no matching 350 but that is down the road ideas.


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## bigD (Jul 21, 2016)

I'd think twice about putting a Voodoo cam your stock, and possibly tired 350. 

Those cams are designed to increase cylinder pressure. Your stock engine may not react well to that extra pressure.

Since you have mentioned the possibility of a big engine later on. I think it might be a good idea to not spend any more than you have to on the 350. Buy only parts you can later use on the bigger engine.

But, if you really wanna make some power with your 350 block, you can build a stroker, similar to the 383, in the posted link. The guy who built that engine and sold those parts is no longer in business. However, Butler sells both the 4" stroker assembly, and a 4.25" assembly. The 4.25 assembly will put your 350 over 400 cubes, and make lots of low end torque, which should make plenty of tire smoke. 

http://butlerperformance.com/c-1234...es-stroker-kits-350-blocks-383-413-cu-in.html

But, the reason that very few build a 350, is that you can build a 400 block stroker cheaper, and get a lot more torque & power.


"... edelbrock 650 avs that we just tuned but still gotta tweek the vacum secondaries. Slight hesitation when kicked in..." 

That might be one reason you can't spin a tire. I recommend a GOOD Q-jet. The 325hp 350HO engines had a 750 Q-jet. With a Q-jet you don't have to worry about having too much cfm. They provide the engine what it needs. Even some of the little 301 engines came with a Q-jet, as did some of the OHC inline six engines. When they are built and tuned right, a good Q-jet is hard to beat.IMO


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## bigD (Jul 21, 2016)

"...wanting to install a ram air cam like in the 69 350 ho..."

That cam your referring to is sometimes called an 068 cam. It was indeed used in some 400 ram air engines. Was also used in some 455's. Melling & others sell an 068 clone.

Engine Camshaft-Stock MELLING SPC-7 fits 63-66 Pontiac Catalina 6.9L-V8

The Summit 2801 is sort of a higher lift version of the 068 cam.

https://www.summitracing.com/parts/sum-2801


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## KowalskiCW (Jul 11, 2016)

So yea I know there is more to the 1 wheel fail than I shared. The PO put a high rpm cam in and never matched a torque converter to it. Still has stock converter and 3.08s I believe. I have a 2000rpm B&M torque master sitting in a box and a shift kit on order. I hope to install a new rear-end with 3.31 or 3.55s in it at some point with posi but that's a later date thing. I need to change out the cam for a more normal operating range cam but this will all take time. 
It also has a crap Edelbrock carb and none matching intake. I want to go back to a Q-jet from this guy SMI CarburetorSMI- Sean Murphy Induction
My buddy used his and can't say enough good things about them.
Right now I just want the compression test done right and the torque converter and shift kit installed. 
The shop by me wants $700 to install the torque converter alone. Does that seem like a lot? I wish I had a way to get the tranny out in my garage but I don't at this time or I'd do it myself.


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## KowalskiCW (Jul 11, 2016)

Redman how did the install of those Pypes go? I've been looking at those too. I have some rusted ass stockish dual exhaust on mine that has holes all over. That system is cheap on the price spectrum but reviews have been good so far. Any droning?


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## REDMAN (Feb 18, 2015)

I have only intstalled the head pipes and muffllers but so far very happy besides the pass pipe is to close to the tranny pan but gonna take it to a shop to have it bent abit. I didnt purchase the kit because at the time of purchase they had the x pipe on sale as well as the head pipes thru summitt and thought I would piece it together in time. My old exhaust was just pieced together like you wouldnt believe and kept falling off. Anyway after it was all said and done the price came out the same except I couldnt find anyone who carried just the pypes tailpipes so ordered flowmaster tailpipes instead thru summitt. Should be here any minute. Drone is not bad at all considering there is no tailpipes or turn downs. Mufllers are clamped with band clamps right off the headpipes and sit just under the front buckets for now. Sounds much better than the flowmasters 44s I had on there with less drone. Im also gonna order the repop 69 exhaust tips from pypes because they come in the 2 1/2 in. not like the originals that are 2 1/4. My only problem I see is mounting the muffler hangers. Having trouble finding a good pic of how they bolt up. I bought exact repo hangers from summitt as well made by pypes. I will update once everything is in place.


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## bigD (Jul 21, 2016)

"...The shop by me wants $700 to install the torque converter alone. Does that seem like a lot?..."

That's OUTRAGEOUS ! :surprise:

Try to find some local drag racers. There are usually some of them that do mechanic work on the side, to make extra racing $$. I'd say that job shouldn't cost more than $200 max. Hey, back in the day, I'da been glad to do it for $100. But, I reckin everything was cheaper then. 


"... I have a 2000rpm B&M torque master..."

I'm sorry to tell you, but that converter is not worth using. A stock converter will stall nearly that much. You want gain a thing. I once bought a B&M Holeshot converter. I couldn't tell that it stalled any higher than the stock converter. 

In order to see a real difference behind a weak 350, you'll need at least a tight 10" converter, which will actually flash stall to at least 2500-2600. An engine with more torque will make a converter stall higher. So, with your 350 you may need a converter which is advertised to stall at least 2800.

There are a lot of cheap converters, in this range, on Ebay.

GM TH350 TH400 10" Torque Converter 2700 3000 Stall RPM Jegs 60401 | eBay

TH350 TH400 10" Performance Race Torque Converter 2600 2800 Stall | eBay

http://www.ebay.com/itm/2700-3000-S...ash=item58a3fdfa45:g:T9wAAOSwAvJXBoyb&vxp=mtr

Allstar Performance 2700 3000 RPM 10 in TH350 400 Torque Converter P N 26900 | eBay


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## KowalskiCW (Jul 11, 2016)

Damn serious? I called B&M and asked them and described my set up to them. Although without knowing the exact cam they couldnt for sure say but they said 2k would be a safe bet. Weird...I don't know if I can return it to Autozone or not but I guess I'll try. I'll look into the higher stall.

I'll definitely ask around for the install because I thought that seemed insane. I'm new to this city so I don't know enough car people yet like I did in the last place I lived but I'll ask around! Thanks 

As for the piecing together the Pypes stuff I hope it all works out and glad to hear the drone isnt bad an its all gone together pretty well. I'll have to put that on my list....my ever growing list haha


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## PontiacJim (Dec 29, 2012)

"I've been noticing quite a bit of smoke at start up lately that eventually goes away, so that's what prompted the check."

Might just be you need new valve seals. They are rubber O-rings and dry-out or rot away and this allows a little oil to seep down the valve stem, past the valve guides, & into the cylinder, typically after you turn the car off and it sets. On start-up, you get the oil smoke because the oil has entered the cylinders and then clears up after a little driving.

New ones can be installed easy enough and may help your condition.


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## KowalskiCW (Jul 11, 2016)

So the other complaint about my car is the extremely firm brake pedal feel. Also some pulsing so I brought it in to get the rotors resurfaced and they did some checking and told me my cam is pulling such high vacuum that there is none going to the brake booster. I knew that cam was a piece of crap for this car. So now I have to replace that if I want any sort of pedal feel.

Also good to know about the valve seals. Guess a new cam/lifters and valve seals hell maybe even a full valve job is in order. Like I've said in other posts I don't think its got hardened seats as I've had some pinging issues only to be solved with 93 octane gas and some octane booster. Timing is at 30 deg and runs great til putting load on.


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## 1968gto421 (Mar 28, 2014)

Gee, Kowalski, aren't cars fun???? Have you been able to get any warm engine compression readings yet? Although the readings may be lower than actuality because of the cam holding the valves open longer. Valve guide seals can be done without pulling heads using an air compressor fitting in the spark plug hole to keep the valves closed. If you do have a valve job done, remember Pontiac used 30 degree valve seats rather than 45 degree like Chevy. Find a GOOD machinist who knows this stuff.

Also, hardened valve seats do not affect pinging, detonation does-----fuel/air mixture igniting too soon because of wrong ignition timing, carbon buildup igniting the fuel/air pre-maturely, hot spots on the piston or combustion chamber, etc. etc.

Keep asking things, there are many good and knowledgeable people here willing to help.


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> So the other complaint about my car is the extremely firm brake pedal feel. Also some pulsing so I brought it in to get the rotors resurfaced and they did some checking and told me my cam is pulling such high vacuum that there is none going to the brake booster. I knew that cam was a piece of crap for this car. So now I have to replace that if I want any sort of pedal feel.
> 
> Also good to know about the valve seals. Guess a new cam/lifters and valve seals hell maybe even a full valve job is in order. Like I've said in other posts I don't think its got hardened seats as I've had some pinging issues only to be solved with 93 octane gas and some octane booster. Timing is at 30 deg and runs great til putting load on.


I think you mean the cam is pulling NO vacuum. If it were pulling high vacuum, you'd have no problems.

Changing the cam will help your vacuum. It may not help your detonation, but might if you select the right cam. Compression is what causes the detonation (which dictates what grade of gas you will need to run on). Changing the cam may not solve this. It is possible to use a slightly thicker head gasket to lower compression, but you need to know what the cc's are of your head. A thicker head gasket may open up the "quench area" above the piston and create another opportunity for detonation/pre-ignition to come back and bite you.


Redoing the heads may cause problems. Now you have a tight sealing head, it may overtax the rings and you'll have blow-by.

Personally, if you are going to rebuild the heads, install new cam/lifters, possibly a new timing chain/gears, (you'll want to replace the harmonic balancer if it is stiff factory) and gaskets, why not just pull the engine and rebuild it right and be done with it?

Otherwise, to just do it cheap until you can afford a rebuild or upgrade to a 400CI, just install a better cam/lifters, new valve seals with heads on the car, and leave it at that. :thumbsup:


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## KowalskiCW (Jul 11, 2016)

These cars are fun! Just wish I had the budget to do what I want RIGHT NOW! Haha don't we all.

So I got the my car back from the shop and they tagged me with new lower ball joints, repacked wheel bearings, new brake pads and resurfaced drums and rotors and now my brake pedal feel is perfect! So that's taken care of haha.

As for the cam/lifters/valve job its all "plans" only if my compression checks out. Either way it's a high mileage original never taken apart lower half with 116k on it. I have been checking around like crazy in MN for a used 400 or 455 and cannot find anything. So far the wife is starting to put the brakes on my car spending as I've only had it since May haha. I still plan on checking the compression but might not get to it til next week as I'm heading on a fishing trip this weekend.

I'll keep you posted.

Good to know about the 30deg valves. I also thought hardened seats helped with unleaded fuel usage. Oh well I'd have it done no matter what if the time comes. As far as I know the timing is perfect according to that shop which I am slowly beginning to wonder if I can trust as you guys feed me different info than their "resident classic car guy" who's been working on my car.


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## REDMAN (Feb 18, 2015)

Im glad to hear you got the brakes fixed. Was it the same shop that wanted to rape you on the torque converter swap? I didnt get my exhaust on as of yet. Hurt my back before I got started. Going to the shop next week after I get my pypes gto exhaust tips delivered. Im still on the cuff in regards to the gas tank but the one on ebay from tomsclassics is looking better for the price and comes with sending unit. Seem to have good feedback but if anyone else has good or bad expieriences with them im all ears.


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## KowalskiCW (Jul 11, 2016)

It is indeed the same shop. They are just stupid convienent(close to my house and have a free shuttle service) I'm searching and asking around.
Sorry about the back but I'm hoping you can share a sound clip or something when your exhaust is done.
I'm having trouble with my fuel gauge too haha just another thing. Mine reads over full til I get down around a 1/4 tank then it reads around 1/2 a tank. The tank appears to be aftermarket new but I guess that doesn't mean the sending unit is. It worked fine the first few months but recently stopped reading correctly. Just another thing to check into.


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## REDMAN (Feb 18, 2015)

Not an expert on the fuel gauge but from what I have read here on the forums if its reads empty all the time its a ground if full its the wiring and or gauge.Sounds to me like the fuel sending unit needs to be replaced but mabe someone with more knowledge can chime in. Im replacing both sending unit and tank soon but gonna check all the wires and connections plus the gauge once tank is dropped. Im lucky and happen to have a very good friend who is a master union electrician that is gonna help me diagnose my problems once I drop the tank and new one aririves. Nothing worse than not knowing how much gas you have or if you fill it past half its leaks all over.


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## REDMAN (Feb 18, 2015)

Got the complete exhaust installed today and I am very happy with the performance of the 2 1/2 in exhaust. I can finally get the rear tire to burn off the line without brake torquieng and I am running 278 stock gears. No drone with the pypes street pro mufflers and x pipe but way to quiet for what I like but seems the back pressure is much better now. I will prob leave it alone for now but might ck into the more aggressive mufflers down the line. The shop charged me 100.00 and that included bending the down pipe away from the tranny. Sounds good to my friends but not as aggressive I would like but very nice system for the no matching 350 which Im keeping by the way. Rear main seal leak turned out to be loose pan bolts. Car really screams down the road for a 350 and I have had some performance cars including 400 gtos.


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## KowalskiCW (Jul 11, 2016)

Man good to know. I will save my pennies! My gas tank thing is not consistent. I ran it to almost empty and the needle worked normally. Now I filled it and it actually isn't past full like it usually is. Maybe I hit a bump hard enough to have it correct itself haha. We'll see how it goes before I have to store it for winter. Stupid MN weather.


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## KowalskiCW (Jul 11, 2016)

So with my tired 350 I decided to just keep the motor, but rebuild it. Nothing too crazy but want opinions. Working with a budget as is everyone what do you guys think of this package of stuff? Also anyone have a thought on how much an engine shop would charge to tear down and build up the motor using parts I'd supply? Rough estimate? I'll be pulling it, stripping the paint off/painting and reinstalling with a buddy.
Engine kit
https://www.summitracing.com/parts/fem-mkp621d-311
Cam kit
https://www.summitracing.com/parts/cca-k51-232-3
Rocker/pushrod
https://www.summitracing.com/parts/cca-rpm1451-16
Of course I'd change to threaded studs during the rebuild if feasible as well.
Top this off with the Pypes X-system and some headers.


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## bigD (Jul 21, 2016)

I wouldn't buy a kit. I'd buy individual parts. You don't know what your overbore will be, or your bearing undersizes. The best cast pistons are probably the SP 357P. The cheapest forged pistons are from Auto/Tec, for around $500 shipped. 

If your overbore is .030 here are some pistons & moly rings.

http://www.ebay.com/itm/Sealed-Powe...ash=item2364e3a18b:g:cioAAOSwv9hW5~rn&vxp=mtr

https://www.summitracing.com/parts/slp-357p30/overview/make/pontiac

https://www.summitracing.com/parts/pcr-40076cp-030/overview/

https://www.summitracing.com/parts/slp-e-245k30/overview/

And there are much better cams. That one is a single pattern, with a 110 LSA. On a fresh rebuild, the small 256 Voodoo that was mentioned earlier, might be a good choice. OR, to save a few bucks, you could go with the Summit K2800 cam & lifter kit. 

http://www.lunatipower.com/Product.aspx?id=1774

http://www.jegs.com/i/Crower/258/66...3Q0XZ8a7NUNyFhaD_U4xHOs7i-NITnmmWbRoCJ_jw_wcB

https://www.summitracing.com/parts/sum-k2800

The Melling M45DS oil pump is sorta std equipment for most street Pontiac engine builds. That's what I used in all my Pontiac engine builds.

https://www.amazon.com/Melling-M54DS-Replacement-Oil-Pump/dp/B000C4PO6E

I don't think there are any 350 Pontiac head gaskets made now except for the high priced brand. Most guys just use the Fe-Pro gaskets which were made for 400 & 455 engines. The bore size is 4.3", which is much larger than the 350 bore size. This will reduce compression. You can go with thinner Cometic gaskets, to increase compression. If your deck height is zero, you can go with .040 thickness. If it's .005 you can go with .036 thickness, if .010 go with the .030 thickness, & if over .010, go with .027 thickness. This will help keep the quench distance close to the recommended .040 number. These gaskets can be made for blocks with or without the chamfers at the top of the cylinders. It is said that the deck needs to be a certain smoothness, for these gaskets to seal correctly. So, you need to make sure your machine shop can produce this type deck surface. 

http://www.jegs.com/i/Cometic-Gaskets/245/C5710-040/10002/-1

http://www.jegs.com/i/Cometic-Gaskets/245/C5710-036/10002/-1

http://www.jegs.com/i/Cometic-Gaskets/245/C5710-030/10002/-1

http://www.jegs.com/i/Cometic-Gaskets/245/C5710-027/10002/-1

If you plan to use a Voodoo or similar cam, I'd have screw-in studs installed in the heads. If your budget can stand it, I'd also go with new stainless valves. There are 2 ways to do the screw-in studs. I think the most popular way is to use the ARP studs which have a 7/16 top, but 1/2" base threads. With these, you simply pull the old studs and tap the holes for the new studs. If the holes are not deep enuff, some will have to be ground off the bottom of the ARP studs, since the base thread portion is longer than stock studs. The other way is to pull the studs and have 7/16 heli-coils installed. Then you can use the BBC type studs, which have 7/16 base threads. BUT, since it will probably cost $200 or more to do the screw-in stud thing, I'd recommend buying some good 6x-4 or 5c-4, or the late '73 & '74 #46 heads. All these heads have screw-in studs and factory hardened valve seats. 

http://www.jegs.com/i/ARP/070/290-7201/10002/-1

https://www.amazon.com/ARP-290-7201-Rocker-Arm-Stud/dp/B001T6CRDC

http://butlerperformance.com/i-24452864-arp-7-16-x-1-2-rocker-stud-kit-arp-290-7201.html



"...anyone have a thought on how much an engine shop would charge to tear down and build up the motor using parts I'd supply? Rough estimate?..."

That price can vary WIDELY. Some prices are reasonable--MANY are not. AND, here is the best advice: don't have it built by a shop that has very little experience building Pontiac engines. A Chevy shop can REALLY mess up a good Pontiac engine. 

But, if I had to make an estimate, I'd place it at $1000-$1500 just for machine work & labor.


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## KowalskiCW (Jul 11, 2016)

Thanks BigD for the info. I'll research those parts and start compiling my laundry list. I don't want an insane rebuild($ or HP) but I do want more power and reliability so if some parts are better than others and cost a little more I'll do it.
I also need to start looking for Pontiac builders. I've met a couple GTO drivers around the area so I'll start with them.


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## PontiacJim (Dec 29, 2012)

OK, you are going to like this. The 350CI, as I still feel, is a great engine with much potential, but is often over looked.

Got an article on a *1968 Tempest* (much like your Custom S), 2-dr HT, with the 350 HO/4-speed/3.91 posi, G70 x 14 tires. The car was given the Bobcat treatment: Q-jet adjusted for performance, stock HO heads (big 2.11 valve heads) milled to 61cc's, heat crossover filled/plugged, .020" thinner head gaskets, vacuum advance plugged & distrib. set up to be all in at 2200 RPM's, dwell adjusted to 30 degrees, rocker arms adjusted for 0 lash and locked down with polylocks. The engine will rev well past 6000 RPM's, but kept to an optimum 5700 RPM's.

1/4 mile time: stock tires - 14.3 @ 99.78 mph.
1/4 mile time: slicks - 13.70 NA mph. :thumbsup:

NOW lets look at the *1968 GTO Ram Air 400.
*
Rated at 360 HP @ 5400 RPM's, shifting for the test was @ 5,800 RPM's.
4-speed transmission, 3.91 posi. (same as the above Tempest)

1/4 mile time: stock G70 x 14 tires - 14.53 @ 99.70 mph

A pretty good comparison. The Tempest had a Bobcat tune versus the GTO which had more cubes/torque, Ram Air package with bigger cam & better heads. Slicks would no doubt be a big help for the GTO, but it goes to show how potent the 350HO package can be when matched against the stock RA GTO.

And, for another comparison, Royal Pontiac's *1968 GTO* Bobcat tuned/prepped *428CI*/TH-400/3.55 posi in street tires pulled a 13.8 1/4 mile @ 104 mph.

See any potential in the 350CI? :yesnod:


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## bigD (Jul 21, 2016)

Yeah, there is no doubt that the 350 has potential. There are 350's using #46 & #6x-4 heads that are running 10's & 11's in NHRA Super Stock & Stock racing.

Bill Rink has a '74 GTO Super Stocker, which runs 10's with the #46 heads. Mike Morgan's 10 sec Super Stocker is a '77 Bird, which runs a 350 with 6x-4 heads. Mike qualified #8 , and Bill #23 at a recent national event.

ST. LOUIS - Super Stock Final Qualifying, Session #2 Order

There is also a '74 GTO Stocker, and several '77 Bird Stockers running real quick with the low compression 350's. 

At a recent div 5 race, a '74 GTO Stocker an 11.19 & qualified at #19 .

LODRS 5-6 - Stock Eliminator Qualifying, Saturday Final Order

There are some '77 Birds that have set several Stock national records with the 350/6x-4 head combo. Obviously these serious drag cars have lots of mods you can't run on the street. But, they do show the potential of the 350 Pontiac engine. 

The 350HO engines in '68 & '69 are the only high performance 350 engines Pontiac built. Most of the rest were very low performance, low compression engines with very small cams. And, in some years they were 2-barrel only. But, if you increase the compression a little, and use the correct cam, gears, and other parts, the 350 can be quite peppy. :smile3:


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## KowalskiCW (Jul 11, 2016)

As much as that does make me happy about the 350 haha it isn't what I'm going to able to do with mine I'm sure, on my budget anyways. Mine is the stock low compression(I believe 8.8 or 9.2 350) 47 heads 2 barrel(which is now a 4 barrel edelbrock with a performer rpm intake and some stupid cam from PO) I'm not sure new heads are in my budget but I'll look for 6x heads and see. I'd really like to see 350hp 400tq numbers if possible that runs nice and is reliable. It's also a stock TH350...but big budget plans are to swap for a Tremec hydraulic 5 speed but for now the Auto will stay.


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## bigD (Jul 21, 2016)

"...I'd really like to see 350hp 400tq..."

Gonna need some compression and the right cam to make 350hp. The '69 350HO was only rated at about 325hp or so. And it had over 10:1 CR, #48 heads, and the 068 cam. With that much compression today, you'd need to mix in some race gas, or Torco Accelerator octane booster, or use E-85. 

MIGHT be able to get near 350 with 9:1 CR and a steep ramp cam, like maybe a 262 Voodoo, and a GOOD Q-jet, like an SMI model. Then you might need a tight 10" stall converter, that will flash to about 2500-2600 rpm. That's why most go for more cubes. It's just easier to make power, at a lower rpm.


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> As much as that does make me happy about the 350 haha it isn't what I'm going to able to do with mine I'm sure, on my budget anyways. Mine is the stock low compression(I believe 8.8 or 9.2 350) 47 heads 2 barrel(which is now a 4 barrel edelbrock with a performer rpm intake and some stupid cam from PO) I'm not sure new heads are in my budget but I'll look for 6x heads and see. I'd really like to see 350hp 400tq numbers if possible that runs nice and is reliable. It's also a stock TH350...but big budget plans are to swap for a Tremec hydraulic 5 speed but for now the Auto will stay.


Point is, the 350CI has potential. Potential of any engine IS ALWAYS a by-product of cash. The 350 HO engine with the Bobcat kit is by no means a big investment - cast piston/rods, factory 068 cam, the factory #18 heads(*MY MISTAKE* - these were 1.96" intakes, 1.66" exhaust. 1969 used the #48 heads with bigger valves) factory point distributor, etc.. The killer is indeed the compression as you aren't going to run the kind of compression gotten in the article (around 11 to 1). With the right cam, 8.6 - 9.0 compression will work just fine. You wouldn't run a 3.91 gear for a street driven car either.

Keep in mind that the larger 2.11" intake valves will require that the top of the cylinders be notched for valve clearance, something done by the factory on the 1969 350 HO engine. So you could find a set of the 6X heads, but you want to get with a good machinist/engine builder who can work with you on checking these dimensions. You can also fit the #47 heads with 2.11" valves easy enough, but, I would stick with the stock 1.96's and do a good 3-angle valve job and add screw-in rocker studs. Keep in mind that the earlier 389CI & 421CI engines had a 1.92" intake and did just fine. The later 1.96's found their into anything from the 350CI to the 455CI.

My Opinion: Realistic HP might be near 300 with the lower compression and more like 325-340 on the torque. More can be had with the larger valves & higher compression.

Of course cubic inches rule and a step up to a 400 or 455 will provide more HP & torque. 

Again, its all about what you want or have available plus your budget & cash available. :thumbsup:


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## REDMAN (Feb 18, 2015)

*Hp*

I have to admit I love my no matching 350 with 47 heads,650 edelbrock carb, performer intake, 2 1/2 pypes exhaust with x pipe and originaly thought it was stock but beginning to wonder with the way it has been performing possibly it is not stock but I had to fix the timing chain two months ago and it was a gm nylon tooth timing chain so wouldnt think anyone would rebuild an engine and not change the chain The compression is real good and gets from 0 to 70 in seconds ,(doesnt burn any oil, no smoke, no knocks or ticking) makes me wonder. Wish I knew more about the motor but gonna leave it alone until problems arise and will decide then what to do. I love the way it runs for now since upgrading the carb and exhaust. If I was looking for more hp or trq I would go with a 400 which I might in the future and keep the original motor since its no matching even though po cloned it to a gto from a custom S but I was originally looking for a custom S but love the look and have decided to leave it as a clone for the near future but do not claim it to be a gto even though I get tired of telling everyone its a clone. Man that gets old but im honest. LOL. Anyway geuss Im saying a pontiac 350 can perform well and modestly because it is a pontiac. Not a chevy, olds, buick etc which I have had all three and would own a pontiac over any of them even a 350. The attached pic is from the original ad my buddy bought the car from. I did not do the frame off. Car was from detroit during frame off if anyone has info on it , Im def all ears for sure and would love to learn more about it. >


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## KowalskiCW (Jul 11, 2016)

Man you guys rule. I needed to hear the realistic numbers and I can live with that. This forum has been better than any other forum I've been a part of, Camaro, 3 different motorcycle forums, you guys rock. I am taking many notes and using this all to plan smartly. I too want to keep my numbers matching 350 and just want to get the most out of it but keep it streetable. Keep the info coming! I will definitely look into valve changes if that could get me better flow. I've also always wanted to try my hand at polishing and gasket matching the exhaust and intake runners but not sure if it's worth the time or smart to do. I find myself fairly confident with air tools and the such. Thoughts?


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> Man you guys rule. I needed to hear the realistic numbers and I can live with that. This forum has been better than any other forum I've been a part of, Camaro, 3 different motorcycle forums, you guys rock. I am taking many notes and using this all to plan smartly. I too want to keep my numbers matching 350 and just want to get the most out of it but keep it streetable. Keep the info coming! I will definitely look into valve changes if that could get me better flow. I've also always wanted to try my hand at polishing and gasket matching the exhaust and intake runners but not sure if it's worth the time or smart to do. I find myself fairly confident with air tools and the such. Thoughts?


Keep taking notes! :thumbsup: Read through this forum and it'll give you a little more info for a good build on the 350CI: Need advice on a Pontiac 350 engine

Doing your own porting work is not too difficult if you can use a high speed grinder and have the right cutters. I do all my own work. Nothing real fancy, just gasket match the intake runners, smooth out all the rough casting lines/bumps, and equalize the intake runners at the pushrod bulge. On my latest heads, I did go a little more and opened the bowls, did some blending, and boat tailed the valve guides as found in the Jim Hand Pontiac book - a lot of work and hours. But just a nice basic gasket match/clean-up will improve flow along with a good 3-angle valve job.

Ames sells the old Pontiac Engine Design & Blueprinting by the former H-O Racing. Ton of info that can help anyone. https://secure.amesperf.com/qilan/Detail_Web?part_num=W112&order_number_e=NDE5NDYyMg==
&web_access=Y


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## bigD (Jul 21, 2016)

"...I too want to keep my numbers matching 350 and just want to get the most out of it but keep it streetable..."

If you really wanna get the MOST out of it, and have the $$$, a stroker assembly is the way to go. Butler sells 4" & 4.25" stroker assemblies for the 350 block. Hey, either of these, with a forged crank, could make a high power, but streetable engine, with a 350 block. :smile3:

http://butlerperformance.com/c-1234...es-stroker-kits-350-blocks-383-413-cu-in.html


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## KowalskiCW (Jul 11, 2016)

So with my #47 heads...what is the best thing I can do to improve those heads then? I'd really rather not start diving into other heads. To get the bigger valves in what do I need to have done? Is it worth it on my 350? Or would just a good port matching and polish do a decent job? I'd rather spend the money on some decent components like roller tip rockers and stuff than some unknown condition heads I guess.


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## bigD (Jul 21, 2016)

The 47 heads are good heads when correctly built. For a 350, you don't need the big valves. A mild gasket match of the intake ports, of heads and intake, don't hurt anything. But, porting is unnecessary. Other than a GOOD, complete valve job, including bronze guides, and good valve stem seals, by somebody who knows what they are doing, the main thing the heads need are screw-in rocker arm studs. 

Most guys go with the ARP 7/16 studs which have 1/2" base threads. The stock studs are pulled & the holes tapped for the 1/2" base threads. I've read that some holes are not quite deep enuff, and some has to be removed from the bottom of the studs, so that they won't bottom out. 

https://www.amazon.com/ARP-290-7201-Rocker-Arm-Stud/dp/B001T6CRDC

Arp Pontiac V8 1964 Later 7 16" w 1 2" Rocker Arm Stud Kit Arp 290 7201 | eBay

ARP 290-7201: 7/16" with 1/2" coarse, Pontiac (1964 & later) B : 2.000" | JEGS

Another way which some recommend is to have 7/16 heli-coils installed in the holes. Then you can use any stock Pontiac or Chevy BBC studs. The BBC studs come in several lengths, and price ranges. Unless you run full roller rockers, I think a top length of 1 3/4" is long enuff. If you know some long time BBC guys, you might be able to get some used BBC studs real cheap or free. 

http://www.jegs.com/i/JEGS-Performance-Products/555/20582/10002/-1

I assume that the conversion to screw-in studs will cost over $200 total, no matter which way you do it, depending on machining costs.  If you want to avoid this expense, you can probably just run a small stock type cam(such as an 067 or 068 clone), with just over .400 lift, and get by just fine, with press-in studs. But, if you go with a bigger cam & stronger valve springs, the screw-in studs are a good investment.


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## PontiacJim (Dec 29, 2012)

*bigD* has it right. The stock press-in studs would be OK with mild cam, but the screw-in stud conversion would be preferred. The "old" HiPo engines used to have the studs pinned with a roll pin - this might be a cheap alternative.

On the porting, if you choose to try this yourself, you are simply cleaning up the ports, not opening them up or contouring them any - just cleaning any casting lines/bumps/etc.. A course sandpaper porting roll will do it. You *do not want* smooth, you want slightly rough to keep the air/gas mixed. Port matching is done with the intake gasket. You don't have to equalize the intake ports at the pushrod bulge, it is something I did and it wasn't (for me) to difficult using a "inside snap gauge" to get them all equal and then contoured/polished with the sanding roll. I use a carbide bit and high speed grinder as it whittles the metal away faster than follow up with the sanding rolls. I am sure a You Tube video has got to made on this. But.......you can leave the ports as is and be just fine.

I like stainless steel valves if you replace yours. There is the argument to add new hardened valve seats due to the use of unleaded gas. I read the SS valves are supposed to also work. Never had any problems with valves sinking, but I feel it is probably more a problem when you start going really big lifts and big spring pressures.

The 3 angle valve job is your biggest flow improver on the heads, so this is a must.

Bronze valve guides are a must- better valve sealing and will true up the valve guides. Don't let any machinist tell you he can knurl the valve guides - its cheap and will not last long.

I like the Viton valve seals over teflon seals, but you will have to mill the valve guides to get them to work. Not a "must have", but an option if you can.

Don't spend your money on the roller rockers. They really are not needed unless you want bragging rights. Rather, just invest in a set of aftermarket 1.5 stamped rocker. They are rugged, accurate in ratio, and trouble free plus saves you money you can put elsewhere in your build.


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## KowalskiCW (Jul 11, 2016)

PJ why do you say don't waste time with the stamped roller tip rockers? I always thought freeing up energy=HP is it really not worth it? All the other info is very helpful so thank you guys.


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> PJ why do you say don't waste time with the stamped roller tip rockers? I always thought freeing up energy=HP is it really not worth it? All the other info is very helpful so thank you guys.


I am no expert on rocker arms nor have hands-on experience as I've only used factory stamped rockers so some of the racers on the forum might chime in here, but.....Many of the articles on the internet will show a HP gain because they typically go from a 1.5 ratio to a 1.6 ratio, or something more than the factory ratio, which is a little bit of journalistic trickery. This always bumps up HP because you are changing the opening rate of the valve, raising the lift of the valve, and adding a little more duration to the cam. Why not just get the bigger cam from the get go? If you compare a 1.5 stamped against a 1.5 roller tip rocker, you may see no HP gain, and if you did it_ might_ get you 3-5 HP at best and this would be at higher RPM's. Think you can feel 3-5HP at the seat of your pants? Not really.

In a race engine, sure, there can be a benefit to use roller rockers, but these are not roller tip, they are the full roller rockers with roller trunion - high dollar, and the aluminum types can fatigue/break over time with the high lift, high spring rates, and high RPM ranges a race engine is built for. The steel roller rockers being the best and will hold up. Remember, race specific cars typically get torn down regularly for inspection - so if anything is amiss with the roller rockers, it is most likely caught early, if not, a broken trunion can release its needle bearings into the oil/oil pan resulting in some bad side effects.

That said, the roller tip rockers won't give you any real HP gains. What they may do is wear less on the valve stem tops because they roll over them as opposed to be dragged over them with stamped factory arms. Factory engines going well over 150,000 miles with stock rockers can't be all that much wear to really worry about. The Comp Cams roller tips still use a pivot ball just like your stock rockers, so no advantage here as you would get with a full roller trunion set-up. Next point taken is the rocker ratio is consistent and more exacting than the factory stamped rockers which are typically lower than the advertised 1.5 ratio and can vary from rocker to rocker. But, the Comp Cams factory stamped 1.5's are what they say and are consistent.

For the 350CI that you have in mind, using the stock heads as modified, I don't think you will be spinning the engine regularly to 6-6500 RPM's. You can of course, but now you will most likely be talking a much bigger bank roll. The Comp Cams 1.5 steel stamped rockers are $96.00 as set. Roller tip Magnum rockers are $150.00 a set. Not really that much in the over-all scheme of things, but if on a budget, the extra $50 would cover a double roller timing chain & gear set.

I myself purchased a set of the 1.65 Comp Cams Magnum roller tips to try out for my 455 build. I will use the Comp 1.5 stamped steel set I already have to break the engine in and get a feel for the performance. I am thinking I will swap the 1.5's for the 1.65 roller tips to see if I notice any power gains due in part to the addition lift - but my heads may not respond well to them, so I'm just looking to play with them to see. I could not seem to find 1.65's in stamped steel or I would have gone that route. The RA IV with its .520" lift and capability to rev over 6,000 RPM's used 1.65 stamped steel rockers - so, were the Pontiac engineers off their "rockers" smilielol on this one when they could have used a roller rocker if they felt the stamped rockers were too weak or going to cause problems?

Just sayin' so you don't think you will get big HP numbers from a roller tip, and just sayin' if you are on a budget. :thumbsup:


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## KowalskiCW (Jul 11, 2016)

Once again you make very valid points. I guess I saw Summit had the 1.52 roller tips with pushrod kit available($263) so I thought a little extra lift might be worth it, but you're probably right, 5hp...who's gonna notice? I do need a new double roller chain! haha I figured I needed to replace all moving parts really except crank and rods so why not? But budget is always a concern.


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> Once again you make very valid points. I guess I saw Summit had the 1.52 roller tips with pushrod kit available($263) so I thought a little extra lift might be worth it, but you're probably right, 5hp...who's gonna notice? I do need a new double roller chain! haha I figured I needed to replace all moving parts really except crank and rods so why not? But budget is always a concern.


FYI. You want to replace the connecting rods with forged rods. Much stronger and insurance against any failures. By the time you install a quality rod bolt like ARP's and then have the rods resized, you might just as well go a few dollars more and get the forged rods so you can sleep at night and don't have to worry about rod failure.

Don't get me wrong, Pontiac rods are very strong and will hold up to some high RPM's. The problems come in when the factory rod bolts stretch due to excessive RPM's and the rod can bow inward at the parting line acting like a squeegee wiping off the needed oil at the bearing and eventually bearing failure. You can rebuild them and you can save a few bucks, but......

$298 a set for factory replacement forged rods. http://butlerperformance.com/c-1234...ternal-rods-5140-forged-replacement-rods.html

So keep this in mind. :thumbsup:


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## bigD (Jul 21, 2016)

To me the only advantage to using roller tip rockers is is to reduce valve tip wear. I've had several valve tips to wear down far enuff to need replacing.


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## KowalskiCW (Jul 11, 2016)

Man I didn't think I'd need rods...this budget for parts alone is at about $1700(minus the roller tip rockers and add rods) then throw in another $1500 for machining and assembly oye. I'm sure that's cheap to some but that's getting up there for a budget build. Throw in the SMI quadrajet and I'm at $2150 for parts ha. I still have drive-line issues to resolve like no Posi and super low gearing and tail shaft seal and hell probably a new torque converter and shift kit if not full trans rebuild haha. Damn


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## bigD (Jul 21, 2016)

"....this budget for parts alone is at about $1700(minus the roller tip rockers and add rods) then throw in another $1500 for machining and assembly oye. I'm sure that's cheap to some but that's getting up there for a budget build..."

That's the reason I usually recommend a Len Williams 455 crate engine. For $4800 + shipping, you can have a complete forged rod, forged piston longblock.

455 Long Block


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## PontiacJim (Dec 29, 2012)

bigD said:


> To me the only advantage to using roller tip rockers is is to reduce valve tip wear. I've had several valve tips to wear down far enuff to need replacing.



Stock engine?


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> Man I didn't think I'd need rods...this budget for parts alone is at about $1700(minus the roller tip rockers and add rods) then throw in another $1500 for machining and assembly oye. I'm sure that's cheap to some but that's getting up there for a budget build. Throw in the SMI quadrajet and I'm at $2150 for parts ha. I still have drive-line issues to resolve like no Posi and super low gearing and tail shaft seal and hell probably a new torque converter and shift kit if not full trans rebuild haha. Damn



Pontiac engines are not inexpensive to build and why, sadly, some go the small block Chevy route. As I recall on another post where this was discussed, you could do an inexpensive rebuild, having basic machine work, and doing all your own assembly to include your carb rebuild for under $3K. But, one major problem and this would go up. My iron 7K3 heads, with all new parts & machine work cost almost $1200. I would not expect your heads, if completely gone through, will be a whole lot cheaper unless you try to use as many of the original/old parts. Heads on a Pontiac are one place I don't want to skimp on if you are going for any performance. 

I'd be budgeting between 5-6K and expect it to be closer to the 6K with everything you are looking at and that's with you doing as much of the labor as you can.


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## bigD (Jul 21, 2016)

PontiacJim said:


> Stock engine?



Think about it. With stock type rockers, the rockers SLIDE back & forth across the valve tip. There is nothing between 'em except a very thin film of oil. 

But, with roller tip rockers the roller ROLLS back & forth across the valve tip. That has to produce less friction, thus less wear on the valve tips, as long as the roller bearings are still working properly.


"...I'd be budgeting between 5-6K and expect it to be closer to the 6K with everything you are looking at and that's with you doing as much of the labor as you can..."

All the more reason to consider the Len Williams 455 long block. He furnishes all the parts, machine, & assembly work. He also offers 400 engines a few hundred cheaper. The one he advertises has cast rods. But, he can add forged rods for slightly more. 

http://lenwilliamsautomachine.com/400_Long_Block.html

He can even build you an alum head engine for around $7k, depending on exactly which combo of parts you want.

http://lenwilliamsautomachine.com/400_Edelbrock_Heads.html


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## PontiacJim (Dec 29, 2012)

bigD: "Think about it. With stock type rockers, the rockers SLIDE back & forth across the valve tip. There is nothing between 'em except a very thin film of oil."

PJ: Yep, I get the friction/wear thing. But, you did not answer my question. Stock engine?

bigD: "That has to produce less friction, thus less wear on the valve tips, as long as the roller bearings are still working properly."

PJ: Aha, as long as they are working.

The action of the rocker over the valve tip creates some back and forth scrubbing friction between the tip of the rocker arm and the top of the valve. And the higher the valve lift and the stiffer the springs, the greater the friction. Over time this can cause side wear in the valve guides, tip wear on the end of the valve stems, and worn rocker arms.

Valve stem tips are generally case hardened to prevent mushrooming of the tips by the rockers. If the valves have been ground down in an attempt to get the installed height correct, the grinding may have removed the hard casing of the tip and allowed the rocker to mushroom the softer material underneath the case hardened outer shell.
If worn out rocker arms are installed on good valve tips they can smear the tops and mushroom the tops or round them over.

One of the down sides of roller rockers is that they can’t handle valvetrain misalignment very well. If the rocker arm twists, it may bend the pushrod and/or allow the tip of the rocker arm to walk off the side the valve tip. If that happens the rocker may push down on the valve retainer instead of the valve causing the locks to pop out and the valve to disappear down the valve guide and hit the piston, destroying the engine. However, the Pontiac heads have push rod guide plates which should prevent this and need to be in good condition.


So again, not being a butt, and *in my opinion*, the roller rockers for a street engine don't really offer big benefits over the factory type stamped steel rocker arms. If the OP uses the factory spec'd "068" cam (which will be a tad bit radical in a 350CI), the Comp Cams stamped rockers will do the job and save a few $. It sounds cool to say "I have roller rockers" but if I were building an engine on a budget, the roller rockers would not be on my list of "to buy" items. This is also where the engine builder/machinist's opinion would come in in making any final decision as which way to go. :thumbsup:


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## bigD (Jul 21, 2016)

So, there you have it. There are different opinions about rocker arms. So, everybody must decide for theirself what rockers to use. 

It's sorta like cams. Some say HFT cams are just fine. Others say they wouldn't run anything but a roller.

Or rods: Some say resized cast rods are just fine. Others say they would not build a engine with cast rods. 

Or carbs: Some like the Q-jet. Some call 'em "quadrajunk", and will use only Holley type carbs. 

Or intakes: Some like the stock iron intake. Some think any performance car should have an alum intake. 

Or exhaust: Some like the RA manifolds. Some think any performance car should have full length 4-tube headers. 

Or wheels: Some like the traditional look of 15" wheels/white letter tires. Some like the modern look of large diameter wheels with low profile black wall tires. 

Or color: Some like red, loud yellow, or orange. Some like the more subtle colors, like different shades of silver/gray, tan/brown, blue, or green. 

Hey, I could go on & on & on & on, etc. But, I think the point has been made. Forums are made up of questions, with answers which are many times strictly the personal opinion of those responding to the question. So, those asking the questions should consider all the opinions, then decide what to do with the info presented in those opinions. I suppose that reading differing opinions is one thing that makes car forums interesting. :smile3:


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## PontiacJim (Dec 29, 2012)

Amen. :thumbsup:


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## KowalskiCW (Jul 11, 2016)

Well s**t! haha If we're really talking 5-6k for a slight performance rebuild my wife is gonna put a huge old STOP sign on that one. I knew pontiacs were more expensive but I didn't think 2-3x more than a chevy. That 400 long block now has my interest but I also really thought I'd have a project for the winter in rebuilding but not going to much more than 3k in spending. Guess I've got some serious budgeting to figure out.
I really do appreciate all the input. I can decipher for myself what I want out of this but your cost inputs are really making me scratch my head. I guess I need to start talking to local shops about machining costs from basic to wild and see where I'll land.
Thanks everyone!


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## KowalskiCW (Jul 11, 2016)

BTW I came across heads on CL near me...would either of these help my 350? There are just too many head numbers to know.

Pair 1972 Pontiac 455 bare heads # 7L4 great shape - FREE.
2.11, 1.77 valves, springs, rockers, hardware for above - $50.

Pair 1968 Pontic 400 bare heads #215 . Small valve, great performance set if upgraded. - $50
Misc valves, springs, rockers, guide plates, hardware for above - $50.


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## bigD (Jul 21, 2016)

KowalskiCW said:


> BTW I came across heads on CL near me...would either of these help my 350? There are just too many head numbers to know.
> 
> Pair 1972 Pontiac 455 bare heads # 7L4 great shape - FREE.
> 2.11, 1.77 valves, springs, rockers, hardware for above - $50.
> ...


The 455 heads have big 114cc chambers, which would not provide enuff compression for a 350. They also do not have any end exhaust manifold bolt holes. 

The #215 heads will work. They're the same heads as the '68 #15 heads, which have small valves, press-in studs, and are listed with 75cc chambers. I have a set on a 455. It came in a '74 Ventura drag car I bought. It ran good. Turned 7.30's at our local 1/8 mile track. But, any heads will need a good valve job and screw-in studs, for any type of performance use.


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> Well s**t! haha If we're really talking 5-6k for a slight performance rebuild my wife is gonna put a huge old STOP sign on that one. I knew pontiacs were more expensive but I didn't think 2-3x more than a chevy. That 400 long block now has my interest but I also really thought I'd have a project for the winter in rebuilding but not going to much more than 3k in spending. Guess I've got some serious budgeting to figure out.
> I really do appreciate all the input. I can decipher for myself what I want out of this but your cost inputs are really making me scratch my head. I guess I need to start talking to local shops about machining costs from basic to wild and see where I'll land.
> Thanks everyone!



The 5-6K was in my opinion, the engine, trans, & rear. You can get the rebuild under 3K if you watch your options/upgrades. Essentially, you will not know what you can use and what you will have to replace UNTIL you disassemble the engine. RPM's will dictate the quality of the build, but if you keep your RPM's down, you can go with factory/cast type parts. Do a comparison between cast & forged just to see what savings might be had. 

Things like the crank could be in great shape and only need polishing as opposed to grinding. Again, you can rebuild your cast rods, just want to add the ARP rod bolts. I found cast pistons on Ebay, Silv-O-Lite for $250. Your machinist can advise you on the heads as what to replace and what to keep and give you prices on things like a standard valve job as opposed to a three angle valve job. Stainless steel valves run about $88 a set, so I would replace these, bronze valve guides (it is labor that gets you on these), new springs to match your factory retainers so you don't have to replace these, the umbrellas/O-ring seals often come in the gasket overhaul set, and if you keep you lift reasonable, the press-in studs will be fine. 

The factory "068" cam may be a bit much and the "067" might be a better all around street cam for the 350. Both cams have identical lift, .406" Intakes, .406" Exhaust. Difference is the duration. "067" is 273/289 while "068" is 288/302. The 288/302 duration of the "068" cam would be radical on the 350. It fairs better on the 400 due to more cubes. The larger cam also is designed for upper RPM's and you will lose torque/HP on the bottom end which is where you want it on a street engine. But, there are many cam choices. This is just by example. 

That said, in my opinion, and if I were on a budget, I'd price the cast pistons/cast rod rebuild as option #1 , but lean towards cast pistons/forged rods as option #2 . (you could even get lighter wrist pins to drop a little weight from the cast pistons and the overall rotating mass). Cast pistons will hold up well, and I can't tell you what RPM you can spin it, but with forged rods, I would not have a problem turning 5800 RPM's. I've spun stock pistons/rods over 6,000 RPM's with no ill effect, but this was just short blasts, not running long distance at this RPM. You will also want to replace your factory/stock balancer with aftermarket (about $100) & you will want to balance the whole assembly.

Again, just some food for thought. bigD can chime in on this for some guidance as well. :thumbsup: 

But, the bottom line is, you won't know what you will need until you tear the engine apart and take a look and evaluate. You may even be able to use the old piston and simply hone the bores - I've done this myself with no ill effects.


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## KowalskiCW (Jul 11, 2016)

Hear ya loud and clear. After all that talk I went out and started really searching for possible used poncho engines and came across a huge pontiac lover in the area and he has this for sale. 

1972 Pontiac 455 4bbl engine. recent 030 over complete engine. 4bbl carb, intake, hei distributor, chrome valve covers. 1500.00 

I talked to him for a while and feel he's legit. He was sending me pics of all his GTOs he's done over the years and engines at his personal shop. Made me drool! 

I'm very intrigued after talking to him. With my TH350 10bolt 3.08 open rear end what would I all need to make this swap viable? Everyone says to do it. I just want to know minimally what I could get away with here.

My thoughts were, full exhaust, new engine mounts, trans refresh, auburn posi unit and then just swap things off my current engine that can be.
Thanks


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## bigD (Jul 21, 2016)

Hey, I love a long stroke Pontiac. So, what else an I say but--go for it !

The quality of any engine depends on the quality of the parts, machine work, and assembly. 

IF this engine is of good quality, in all 3 areas, it sounds like a super deal. There have been lots of guys who paid around $1000, just for a rebuildable 455 core engine.

If it has '72 model heads, there are no end holes for the exhaust manifold bolts. So, you'd need either manifolds that do not use the bolts, or some of the L-brackets, made for using headers with these type heads. They are sold by Spotts Performance.

http://www.spottsperformance.com/headLbracket

If it runs good, it will have enuff torque to break the stock intermediate sprag outer race, in a TH350 trans. I know this for sure, because I broke a stock one & a TCI hardened one, with an original '70 455 engine. But, if you keep your 1-wheeler, and use only hard rubber street tires, the 455 may just spin the right rear, instead of breaking the race. I was running big slicks, on the track. 

Also, if you ever run sticky tires, and they really hook up, the 455 can break your 8.2 rear end. The same above mentioned '70 455 broke a Buick 8.2, which I had in my '68 Bird bracket car. Again, this was on the track, with big slicks. 

You mentioned an auburn posi. Don't know who has the best price. Ebay has one for $398 shipped. It's for 3.31 & numerically higher gears.

http://www.ebay.com/itm/GM-8-2-BOP-...ash=item4d2f671f5c:g:qI0AAOSw34FVCIEh&vxp=mtr

Jegs shows one for $385 shipped. This one is for 2.93-3.23 gears. 

http://www.jegs.com/i/Auburn-Gear/109/5420114/10002/-1

I wound up with 12-bolt rear ends in all my bracket cars. Never had any trouble with any of 'em. But they are high dollar parts nowadays. Most upgrades I can think of for pre-'73 A-bodies costs North of $1500. There's the rare 8.5's from the '71-'72 Buick & Olds, with bolt-in alxles. And there are aftermarket 9" Ford rears, for around $2k, or a little less, if you build your own cheap chunk.

But hey, Pinion head is the rear end expert here. So I'll leave the details to him.


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## KowalskiCW (Jul 11, 2016)

bigD I have added those things to my list to make this 455 work. However I do not ever plan on putting slicks on or sticky tires. I love the classic look of my 14's with Cooper Cobras on it. I don't think I have any fear of destroying the trans as long as it's refreshed before doing this do I? I'm not a track guy, I just want to burn some tires now and then and feel cool haha.
Also with the rear end the same thing. I don't think I'll have to worry about it if I'm just running stock Cooper Cobra tires right? I truly don't want to stick money into that stuff except a posi unit and refresh of the tranny unless I break it. Just didn't know if there was a absolute necessary thing that should be done.


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## bigD (Jul 21, 2016)

Lots of guys have got by with stock TH350's & 8.2 rear ends. Maybe you'll be among the lucky ones. 

If you are not gonna upgrade the TH350 to a 36 element sprag, I wouldn't have a shift kit installed. The hard 1-2 shift is what breaks the sprag race. Some go with a mild shift kit & a hardened sprag outer race. 

GM TH-350 TransGo Transmission Shift Kit 1969-1983 (SK350) | eBay

https://www.summitracing.com/parts/ati-355450

th350 hardened sprag outer race in eBay Motors | eBay


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## 1968gto421 (Mar 28, 2014)

KowalskiCW said:


> Well s**t! haha If we're really talking 5-6k for a slight performance rebuild my wife is gonna put a huge old STOP sign on that one.!


I can really identify with your situation. I pray that the PO's of my GTO actually did have the engine rebuilt because if they didn't, I too see a huge old STOP sign (especially since the car had a doors, etc. off paint job and new interior (photo documented), I paid over 20K for it, so....The STOP sign is up. 

PJ and BigD have given you excellent info. tons to sort through. Hopefully your 455 seller had a quality rebuild on that engine and you'll be fine. Member here, Goat Roper, posted his experiences with a bad rebuild on this forum: 

http://www.gtoforum.com/f170/central-virginia-machine-service-cvms-negative-review-106018/

Good Luck and let us know how the 455 deal goes!


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## KowalskiCW (Jul 11, 2016)

So speaking to that I'm having a bit of a crisis now. 
The guy with the used 455 seemed really nice and knowledgeable and has been doing Pontiac engines for 30 years. I was just about committed, then today he started acting weird when I texted him some other questions. He said he wanted to all the sudden add a better cam and hotter heads before putting it back together which would push it out of my budget, closer to the $2100 of this other guy. But he also said I could come see it run and see pics of the inside if I want it as is, So I got leery.
Now there is another guy the has an actual shop and warranties his work for a year after install. He charges $2100 for a fully built '69 400 with either the 262 or 268 cam depending on what I want, but without any of the tins or intake(long block). This sounds fine as all mine would swap but the 455 had it all. Carb, intake HEI and valve covers. The 455 guy is just over an hour away while the 400 guy is about 2hrs away. Both seem extremely competent but the wife is getting worried about my climbing budget now. So I'm not sure what's the right move. 
I think with the 400 I'd be less likely to break other components of the car but the 455 is definitely more bang for the buck.
Thoughts?!


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## bigD (Jul 21, 2016)

I'd be extremely leery of a complete 400 Pontiac long block, for $2100. 

I'd guess it is a 557 block. with cast rods & cast 8-eyebrow pistons. :frown3:

But, IF it is really a '69 block, and has forged pistons, and the warranty is legit, it sounds like a smokin deal. 

Here's a 400, with cast rods, but forged pistons, done right. It's $2000 higher than the price he quoted you. And I assume you could specify no 557 block. 

http://lenwilliamsautomachine.com/400_Long_Block.html


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## KowalskiCW (Jul 11, 2016)

BigD Yea I've seen those long blocks and you're right it does seem a bit odd he'd do it for 2100. He has an actual shop so I'd hope he would realize his shops reputation would be at stake but some people just don't care I guess.
I've been talking to the 455 guy a lot and he really seems legit. He does it out of love for Pontiacs not as a job. He has sent me pics of the engine now all torn down to just the rotating assembly. He took out the cam, lifters, heads off and sent me pics of it all. He said he wanted to make sure it was clean and good before selling it. It looked amazing "assuming he didn't snap pics of some other engine" But he said to come look at it while it's apart and then he'll button it back up and have it ready to run the next time I come and pick it up if I so chose. So I think that the 455 is my route. Can't beat it right? $1500... I'm no dummy when it comes to engines and what to look out for it's just I'm new to the Pontiac world so advice is welcome.


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## KowalskiCW (Jul 11, 2016)

So I went to the guys house yesterday with the 455 and OH MY GOD. Talk about a disease! He is the man to know! He had 60 pontiac engines worth of parts and 7 of them done anywhere from 400 RAM AIR IVs to BUILT 455s. 4 GTOS...2 69's in orange 1 70 in blue and 1 70 in white. This guy can be trusted if anyone so my next question is..the engine he IS selling.
It has a late 72 date code but a big 73 stamped on it on the top does that mean it was for a 73 car? It had 4X heads, but everything was in perfect shape. It's been bored 30 over and has a mild street cam in it. He built it 2 years ago for his client but then the client wanted a huge built 455 so he traded it back in 2 years later with about 3500 miles on it. Now my worry is that it was a smog engine and was only rated at like 200hp back in the day. I didn't think to get the block code while I was there so I'll ask that today. Is there any chance this thing is more rated around the 335hp I was hoping out of a 455 or is this one a waste of time? See pics
Thanks!


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## KowalskiCW (Jul 11, 2016)

pics


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## KowalskiCW (Jul 11, 2016)

So it is a YC code 455 from a 73 car...crap that means it was a 250hp motor. That's frickin lame from a 455. I know that was smog related with the manifold and carb set up which I would be using my performer RPM manifold and a well built quadrajet and some good headers but would I really be around 335hp? He thinks the compression is around 8.9:1 but Rons Pontiac page lists it at 8.1:1 Any thoughts? I honestly do trust this guy knows his stuff. He's been a Pontiac enthusiast since 1971 and is very knowledgeable.


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## Pinion head (Jan 3, 2015)

Have had many '73 Pontiac 455 engines & had quite a few built for customers. Pontiac built a TON of '73 Grandvilles & Bonnevilles & the 455 was standard equipment, thus so many '73 455's floating around. Through the '80's & 90's & into the mid 00's '70-73 455's was out pulling in parts cars & pulling core Pontiac engines nearly every week. Currently have several '73's. 

The '73 455 4bbl Dport engines had 4x-1H heads, huge 114cc chamber heads, that killed C/R. Actual static C/R is closer to 7.5-1, not the advertised number. For many years I wholesaled 400 6X-4 Pontiac long block cores to one of the nations largest Pontiac engine builders. Ocassionally, when i was backed up fairly deep on 455 cores, would alao sell him a 455 core, just preferred to sell the 455's to end users. The recipe for this builders 455 crate engine was 455, bored .030 or .040, then topped with rebuilt 6X-*8* heads, with a Melling RAIV cam & a set of Rhoades lifters. No porting, just stock flow heads. Builds a lot of torque & able to run on pump gas. 

The monster chamber 4X-1h's, 5I's, 6H's are all doorstops. A slightly used '73 455 built with 4X-1H heads, personally I wouldn't give $1500 for, unless I was setting on a pair of fresh rebuilt '71 96's, built 5C's or built 6X heads & could carefully examine the main and rod bearings & crank along with cyl bores, etc.


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## KowalskiCW (Jul 11, 2016)

PH - So you really don't think a 455 with 4X heads bored 30 over and pistons to match as well 3 angle valve job and hardened seats and a 454 lift 224 duration cam and 3500 miles with all new gaskets fully assembled would be worth $1500? Crap really? Even when I add my Performer RPM intake and a new quadrajet?


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## Pinion head (Jan 3, 2015)

KowalskiCW said:


> PH - So you really don't think a 455 with 4X heads bored 30 over and pistons to match as well 3 angle valve job and hardened seats and a 454 lift 224 duration cam and 3500 miles with all new gaskets fully assembled would be worth $1500? Crap really? Even when I add my Performer RPM intake and a new quadrajet?


The bottom line , its a used engine, & having bought a bunch of Pontiac 455's, including ones out of hock in regional "local yocal" machine shops, I have to look at the value of the short block. If the heads had any value, I'd happily agree the combo would be worth more. 

The 4X-1H (455) heads to the majority of Pontiac guys are doorstops. Maybe, if one found an NHRA stock '73-74 455 class racer needing a pair of virgin 4X-1H heads, one could actually keep such a pair of heads from going to the scrapper, but honestly, they're hardly worth the price of shipping. For many years, have had a pair of 4X-1H heads that are fully ported & were built with 7/16" BBC rocker studs. One cyl head is damaged, engine only had a day on the street & due to the absolute Idiot prev owner spec'ing waaay too big a cam (Comp 292), one of the one piece valves kissed a piston top, & the valve head came off & bounced around & boogerd up a chamber. I picked the entire engine up out of a well known Chevy dirt track engine builders shop & went through the shortblock. To mirror image port another 4X-1H head (which I have), then build both heads with 1 piece stainless valves, proper vale sorings, viton seals, competition valve job, my bet us I'd be out $800+. Not happening, the ported 4x-1H will remain a wall hanger.

I've actually sourced several sets of 4X-3H's & 4X-7H's by casting dates for '73 & '74 455 Dport TransAm owners who desired using these 400 4X heads, with their near 15 cc smaller chambers to raise compression of their 455 Dport engines while appearing stock. Problem with these 4X 400 heads, is it took a long time to find pairs in the date ranges needed that weren't cracked. Thats with knowing where over two dozen 400 4X heads were setting stacked in pallets of Pontiac V8 heads.

On the 455 engine in question, for $1500, I'd want to be able disassemble, ck the bearings, both for abnormal wear & for what undersize. Am not a fan of 20-30 cut 455 cranks. Also like to ck the radius & crank end play. Cyl bores, like to measure them very closely. That would mean a quick trip to local friend, prev SuperComp racer, to use his dial bore gauge....something I need to invest in. Would also inspect the rods. Cast rods with cheapee rebuilder rod bolts is not something I like to run across. Have ran across quite a few "good deal" freshly rebuilt Pontiac V8's, that corners were cut in the rebuild process from rod bolts, to piston choice, to cheap rebuilder cams.


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## PontiacJim (Dec 29, 2012)

PH has basically covered it. If you are looking for a street engine, then the 455 is not a bad deal as you describe, "a 455 with 4X heads bored 30 over and pistons to match as well 3 angle valve job and hardened seats and a 454 lift 224 duration cam and 3500 miles with all new gaskets fully assembled would be worth $1500?"

Yes, it has the low compression 112cc heads which give it the 8.0 compression, but, if it has a Competition Cams ground on the 110 LSA, which I believe the specs you have provided are, then it should be a torquey engine. Forget about HP numbers as the 455 is all about torque. The HP numbers for 1972 and later engines used NET horsepower, so it is lower than the pre-'72 HP numbers.

If you were to look at it as a building block for a high performance engine, then $1500 is too high because you would not be using the heads, so you would have to buy & prep a set of heads on top of the $1500 purchase. But if you were to go a step further, if it had stock guts, I would be replacing the rods/pistons with forged pieces and the cam/lifters. So for $1500, I would basically be using the block and some of the key components like pan, timing cover, pulleys, etc.. Kinda expensive for just a useable block. That's what PH is pointing out if the engine were to be used for a performance build.

I also agree with PH in that it is a used engine, even if it has been rebuilt and only has 3500 miles on it. You do not know what parts were used and in what condition they are in. I would want to disassemble the engine for further inspection and check clearances -CYA. Sure, it may be perfect, but do you want to spend $1500, install it in your car, only to have a rapping noise in the bottom end or find you have an oil burner? Better to catch something (if any) now than later. That's what is being pointed out here.

So, it is a good price/deal if you are looking to upgrade the 350CI and are looking for a street engine - providing the engine is indeed good. From a performance standpoint, you would have to change too many things (more $$) to justify the price. A much cheaper 400CI with a 461CI rotating assembly/kit would be a better choice than using this 455 and make it into a street/strip build.

So it is your call.


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## bigD (Jul 21, 2016)

Well, I'll come at this thing from a different angle. PH is coming from a totally different angle than most Pontiac street guys. He has lots of experience with many hundreds, if not thousands of Pontiac engines. He probably now has a very large stash of Pontiac engines & parts, at his disposal. And, he probably knows where he can buy lots more Pontiac stuff for very low prices.

But, MOST Pontiac street guys have very little experience with Pontiac engines, have very few good engine parts, and don't have a clue where they can find a good deal on any good Pontiac engine parts, for a reasonable price. 

So, for these guys, they basically have 2 choices. If they have enuff $$ to do so, they can buy a properly rebuilt engine from a competent Pontiac engine builder. This is definitely the best way.

BUT, for most, a decent long stroke Pontiac engine will cost at least $5k, and even more from most builders, for a complete engine. Unfortunately, MOST Pontiac guys don't have $5k+ to plunk down, for an engine. 

That's why many decide to go with an sbc engine. I figure you can go with a 350 sbc for 1/2 the price of a properly built long stroke Pontiac engine--maybe even less than 1/2. 

So, for the low budget guys, the only way to go with Pontiac power might be to take a chance on a used Pontiac engine. Therefore, if I had $1500 to buy this low compression 455, but knew I would not be able to come up with the price of a good rebuilt engine, I would probably take a chance on it. A low compression 455 is still a lot of fun in a mild street car. Back in 1978, my wife bought a '73 455 4-speed T/A. It was her DD for a couple of years. No, it was not a 12 sec strip car. But, she had one of those--didn't need that much power on the street. The car was plenty peppy and lots of fun to drive. 

Today, on MOST(if not all) of these Pontiac forums, it seems that most everybody recommends 400-600hp engine builds. Having driven quite a few street cars with less than 400hp, I can honestly say, most guys don't need 400+ hp to have a fun street ride. 

But, bottom line: buying any used engine is strictly a gamble. Nobody can possibly know, just by looking at the outside of an engine, how good or bad, any used engine will be. But, if you don't have the skills or opportunity to completely disassemble and examine every part of the engine, you either pass on it, or take a chance on it, as is. This is just the reality of life as an average low budget Pontiac guy.


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## KowalskiCW (Jul 11, 2016)

This is why I come to you guys. So I guess I wasn't clear as I thought. The 350 needs to go and this 455 is a complete replacement that I do not intend to turn into a strip/street monster. I personally did go look at the motor and see everything... Apparently the pictures I posted didn't come thru? I saw it all and it is super clean and tight and cross hatching is even still on the cylinder walls. I rotated the engine with a small wrench and it was smooth and easy. I personally think this engine is worth the money but I had to get opinions. This guy has been rebuilding strictly Pontiac motors for 40 years and assures me it's higher than 8:1 compression. The pistons and rings and valves seals and can and lifters bearings are all 3500 miles old. I guess the net vs gross power is something I didn't know. I didn't get that it went from over 300 one year to less than 250 the next. I do not have a big budget but definitely want torque as I understand torque is where the fun is! Thanks for your inputs and I'm going to get the motor! I'm super excited to have found this guy and had the pleasure of getting to know him. He reminded me of my late father and his passion for classic muscle.
Thanks


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## KowalskiCW (Jul 11, 2016)

Pretty excited. I take delivery of my 462 tomorrow after work! This guy has been awesome. He got it all back together and torqued it all and greased and lubed everything for the break in. Put a new dipstick in, painted it the Pontiac blue/silver I wanted and is bringing it down with an engine stand so I don't have to go buy one. I've seen almost every aspect of this motor in person or pictures and I can't wait. He said it has the notched crank, he says its a good crank, but I honestly don't know anything about that. This thing is gonna thump compared to that tired 350!


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## bigD (Jul 21, 2016)

"...He said it has the notched crank, he says its a good crank, but I honestly don't know anything about that..."

He probably said it is a nodular crank, denoted by the big "N" cast into the counterweight. These are said to be good cranks. Most any 455 crank is plenty good for street builds, up to 600hp or so.

It definitely has cast rods. So don't let it wind past 5500 rpm. 5000 is even a little safer. Unless it has a real big cam, the power will fall off, past 5000, anyhow.


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## KowalskiCW (Jul 11, 2016)

Yea notched my bad. That is what he said. 
It's got a nice street cam he said but either way I've always been told 5200 was a safe RPM for big bore cast rod type motors so that's where I'll stay. Hell I never even made it past that on my 350 out of being too scared to bust a rod in that thing...


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> Yea notched my bad. That is what he said.
> It's got a nice street cam he said but either way I've always been told 5200 was a safe RPM for big bore cast rod type motors so that's where I'll stay. Hell I never even made it past that on my 350 out of being too scared to bust a rod in that thing...


If the rods were rebuilt with ARP rod bolts, it'll go more but........ the 5,200RPM's is safe and where I would limit it. If you do not already have one, I suggest an rev limiter. It is a cheap investment when you are frying tires or nail the gas and the tires break instantly loose and the engine winds up fast. It could save you engine damage, and you'll be able to sleep knowing if your engine tachs out quicker than you can respond, it won't come apart. Even the best of us have had the "over-rev" experience and hold our breath hoping we didn't do any damage. :thumbsup:


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## bigD (Jul 21, 2016)

"...If you do not already have one, I suggest an rev limiter..."


This is very good advice ! I put one on every 455 bracket car I've had. And they saved several 455 engines, when they broke transmissions & rear ends, or just lost traction. 

There are several types. On my last car I used the MSD "Soft Touch" rev limiter box. 

https://www.summitracing.com/parts/msd-8728/overview/

MSD 8728 Soft Touch Rev Controller, 4, 6 or 8-Cyl Engines, Adj w/RPM Modules, | eBay

But, on my current car, I'm using the MSD HEI replacement module, which includes a rev limiter.

https://www.summitracing.com/parts/...4SA5hZ5OfUr9s8vXRNoNN2TfR_T5bk_tq2BoCDMvw_wcB

The Pertronix Ignitor III is an elec conversion for the points type dist, which also includes a rev limiter. 

PERTRONIX III IGNITOR 71181 GM V-8 DELCO,CHEVY,PONTIAC,BUICK,OLDS,CADDY | eBay


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## KowalskiCW (Jul 11, 2016)

Well I got the engine! Everything looks real good except the old man painted it really crappy. I guess I shouldn't have expected it to be nice so I'll have to strip it down and redo that but I actually like doing it. Still driving the Lemans as long as this weather holds out but then I'll start the tear down and swap parts. Everything spins free and nice and seems tight and sealed well. There is that silver graphite looking break in lube on the cam and the lifters have been primed and everything is coated in oil. Couple of glamour shots 
So I am looking into the rev limiter as that's probably a good cheap insurance. So far $1625 delivered(80 miles) w and engine stand was a pretty damn good deal if you ask me as long as it really is a good motor which I believe it is. I'll probably start a new thread for more engine related questions once I dive into the swap!
Thanks everyone so far.


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## 1968gto421 (Mar 28, 2014)

Sounds good. Best of luck with your build. (Only problem i see is transmissions as a 455 can tear them up if they're not built for the torque.)


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## KowalskiCW (Jul 11, 2016)

Yup trans is definitely one of my concerns but I plan on getting it refreshed with the hardened sprag everyone keeps talking about while the engine is out. It needs new tailshaft seal anyways and probably pan gasket. We'll see what budget allows when I get there.

As for checking valve adjustment any thoughts on which process is best for a mild 455 with stamped rockers? 1/2 or 3/4 or 1 full turn after 0 lash? Thoughts on any locktite or antiseize on the studs or nothing at all? The guy adjusted them but for peace of mind I'd like to double check them since I have the time.


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## PontiacJim (Dec 29, 2012)

You stated in an earlier post that the engine had "4X" heads. Here is a read on them: 4X Racing Heads - Tech Articles - Hot Rod Network

The pics you have appear to show the pressed-in studs, but I could be wrong. You don't adjust the press-in studs. The nuts get torqued down otherwise they will back off and you will slip a rocker off which can do damage to the engine.

You should not need the *polylocks* unless you have a problem with the nuts backing off on you. You also need to make sure that they are not too tall and don't hit your factory valve covers. The RPM's you will be turning the 455 should not get you into lifter pump up at high RPM's. If you choose to, here is Comp Cams instruction sheet - read Page 2, Number 7 & 8 : http://www.compcams.com/technical/instructions/files/comp4-118.pdf


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## 1968gto421 (Mar 28, 2014)

Valve adjustment is dependent on the stud. If it is a bottleneck stud (threded part is smaller in diameter than the lower part), you tighten the nut down until it bottoms out, then tighten to 20 ft/lbs and NO MORE then this. If it is the usual 7/16" stud with threads to the head, I generally tighten to 1/2 turn after 0 lash. Loctite is not recommended, nor is anti-seize as this would encourage the nut to loosen. This is for the standard Pontiac nuts on the studs. If you are using something like the Crane Kool Nuts, you would use this procedure (scroll down to the video):

Crane Cams Steel Rocker Arm Nuts | JEGS

Best of luck, you're gonna have one nice LeMans!


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## KowalskiCW (Jul 11, 2016)

Wow now I can't wait to get home and check that because I feel like the guide plates are fastened by the rocker studs. I'm sure it is just pressed cause that's my luck, but looking at the pictures I have seems that they are on the rocker studs. Man that'd be a great little surprise if I had threaded. Nice article PJ thanks.
Otherwise I will just check the torque on the nuts. Do I have to do this when the valves are in the closed position or just go to town because when they bottom out that's that?


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## KowalskiCW (Jul 11, 2016)

well I checked...of course I'm not that lucky. The guide plates and bolted down by bosses in the head casting. No threaded rocker studs here. Dangit


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> well I checked...of course I'm not that lucky. The guide plates and bolted down by bosses in the head casting. No threaded rocker studs here. Dangit


Not a big deal with what you have and what you are using it for. On checking the torque, I have not had to do this as never had a problem on any already running cars or I went with the poly locks. However, in my mind, I think I would have the rocker arm positioned with no lift/pressure on it when I did re-torque the nuts. It would seem to me that if you had any lift/pressure on the rocker arm that this may counter a true torque reading. Just sayin'.


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## KowalskiCW (Jul 11, 2016)

Yea PJ I figured that would be the best results route to go so I'll double check them as the builder told me he torqued them but I like peace of mind.


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## KowalskiCW (Jul 11, 2016)

Is there any reason you wouldn't use one of these flat aluminum valley pans? http://m.ebay.com/itm/AVP01-Pontiac...%3A826fc2c41580a2505514faeffff3c6cb%7Ciid%3A1
I bought one a long time ago for a Pontiac 350 I was rebuilding but I sold that engine before actually finishing it. Any thoughts or should I just swap the original valley pan from my 350?


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## PontiacJim (Dec 29, 2012)

KowalskiCW said:


> Is there any reason you wouldn't use one of these flat aluminum valley pans? AVP01 Pontiac V8 326 350 389 400 421 428 455 Aftermarket Valley Pan Street Race | eBay
> I bought one a long time ago for a Pontiac 350 I was rebuilding but I sold that engine before actually finishing it. Any thoughts or should I just swap the original valley pan from my 350?



Where are you going to fit your PCV valve in the aluminum pan? Did I answer your question? :bannana:


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## KowalskiCW (Jul 11, 2016)

Well they recommended a pcv valve in each valve cover so I assumed that's what I'd do. This engine didn't come with one and I really wanted to keep as much on the 350 to store or sell as possible.


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## bigD (Jul 21, 2016)

Flat valley covers are also available with provisions for a PCV valve.

http://butlerperformance.com/i-2445...utlerperformance.com/search.html?q=valley+pan

The flat covers will not work with the '73-'79 Pontiac iron EGR intakes.


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## KowalskiCW (Jul 11, 2016)

Well I guess since I will probably need new valve covers anyways getting an extra PCV valve that dual acts as a oil filler(which I believe people do) as well as having the flat pan would look nicer and be less than buying a stock valley pan plus getting valve covers I need anyways. Any reason I wouldn't want to do both PCV valves in the valve covers vs the valley pan?


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