# 1977 400cui worth it to swap with my 350 lemans



## SPCMarty (Jul 29, 2011)

Found a nearby 400 engine for $350 but I heard that after 75' the engine quality dropped. 
Ive also considered swapping in a built up 350 Chevy otherwise.


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## Spastik Monkey (Mar 18, 2010)

400 is the way to go

Sent from my MB865 using AutoGuide.com App


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## SPCMarty (Jul 29, 2011)

From what I gather the 77 400 is rated at 200HP stock but can be bought up to earlier 400 specs somehow. And my 350 71 lemans rated at 250hp with a 2 bbl carb (I have edelbrock intake and carb 4bbl) 

My reasoning behind the Chevy 350 is the ease and less expense to build up some bigger HP.


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## Spastik Monkey (Mar 18, 2010)

Yeah. But theres no replacement for displacement


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## Josh.AZ.GTO (Jul 11, 2009)

I wouldn't think of the 75-79 Pontiac 400 as a junk motor. It still is a 400 and if your starting from the block you can build a solid motor.

All 67-79 Pontiac 400s are the same size in displacement, bore & stroke, and main size.


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## Koppster (Jul 27, 2008)

Be wary of 1975-up 400s with last 3 digits of 557 in the block cast code. They have a reputation for being weak:

Found dowel pin in oil pan - PY Online Forums

Form your own opinion after reading the thread above.

Rick


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## SPCMarty (Jul 29, 2011)

Well I hope this engine isn't one of those. There are a number of Chevy 350s to pick from in my area and just this one Pontiac 400 in my price range. 
I hear a 068 pontiac cam is a good upgrade along with edelbrock heads


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## geeteeohguy (Feb 2, 2008)

Small block Chevy's are great engines. In Chevys. They are cheap, powerful, durable, easy to build, and everybody has one. They are also common, uninspired, and cookie -cutter boring. Put a Pontiac 400 in your Pontiac and you will be amazed at how much more power and torque it has over a SBC. Apples and Oranges.


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## Instg8ter (Sep 28, 2010)

what shape is the 350 Pontiac in thats in it?


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## ALKYGTO (Mar 29, 2010)

OP; seems to me that you lack a firm direction from the numerous threads you've started. :willy:

Not being critical, but you've expressed interest in Buick, Chevy and Pontiac engines and you've considered putting pick up truck drivetrain parts in your build. 

It looks like you have a pretty clean Lemans there and I'd hate to see you turn a nice car into your personal nightmare. It can happen, trust me. And it's not a cheap hobby. Set a goal and push towards that. 

Do some subtle things that will be inexpensive and improve the performance, handling and comfort of your car a little at a time. Start by rebuilding the suspension and brakes if they need it, consider a larger swaybar and stiffer springs, shocks. There are a meriad of performance upgrades from the factory and aftermarket for this chassis. :cool

Just keep your eyes open on Craigslist and the local used car lots and salvage yards. I would personally recommend a mild 400 or 455 cu engine with a T400 trans. Look for an old wagon or big Bonne sedan for that. 

Consider the changes you make to increase value and desirablity without ruining the integrety of your car will help justify your investment in time and money and your overall enjoyment . :cheers


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## facn8me (Jul 30, 2011)

agree with the alky up there. Just be patient if you plan on keeping it. Deals are out there. I got my 389 for free. Just got lucky considering I almost bought a couple different engines first. I bought the car and resold minus engine and trans for same price. if it runs and drive right now with a pontiac in it just keep cruising. Maybe even loose a race or two. Always fun toying with them after the big engine is installed. afterall they all look the same size. Plus the exhaust and everything else will just bolt right up. a weekend project at most to swap unlike a potential nightmare. Anything will bolt into anything with a big enough hammer. And many people have IMPROVED many a ford with a chevy engine. Just not needed in this case.


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## Rukee (Feb 8, 2007)

Instg8ter said:


> what shape is the 350 Pontiac in thats in it?


:agree would rather see you spend money on the Ponch 350 then to swap to a chevy 350.


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## Instg8ter (Sep 28, 2010)

if that 350 is anywhere as nice and well taken care of as the rest of the car (my guess a granny car that hardly ever got above 2500 RPM), get a 4bbl manifold and 700 Quadrajet, headers (or RA manifolds), hone re-ring and new bearings, shift kit in the trans, maybe a new set of used heads to pump up the compression (76cc?)....you may be surprised what you get for around a grand and the heads/headers and carb will bolt up to a 400 when you make the switch so they are money in the bank....:cheers


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## ALKYGTO (Mar 29, 2010)

:agree with someone who did it the right way. :cheers


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## SPCMarty (Jul 29, 2011)

I would say I expressed interest in those other engines because I'm exploring all the options and think Pontiac big blocks are pretty sparse. 

I come from the foreign ricer generation of people, I don't know a whole lot about the classics. I know I want more power, ideally out of a big block, but I could live with a built up Chevy 350

My Lemans is in pretty decent shape, I uploaded a pic of it (the good side) and all its mods just having a nightmare putting in the headers. 
The whole horsepower rating method has me confused. Example is the 77 400 really a lesser powered engine than a 71 350 or just appearing that way because of measurement changes.


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## SPCMarty (Jul 29, 2011)

What kind of heads would I replace the 350s with then? From my understanding compression is biggest downfall of the 71 350


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## Instg8ter (Sep 28, 2010)

Pontiac Head Chamber Sizes

any of the heads in the 72cc range with the large valves will get you at around 9:1 CR which will be good for pump gas and make that 354* (actual CI of the Pontiac 350) scream and woop most stock bowtie 350's. The pontiac will have a lot more torque down low, if you want quicker you can change the rear end gear to a 4.10 (you probably have a 2:56) at the sacrifice of highway driving at lower RPM's. You will probably want to put a hotter cam in while your at it as that tells the motor where to make its power. Once you decide your route i am sure the we can make suggestions on part specifications better. The 455 blocks are getting harder to find, the big thing now is to stroke the 400 up to 461+ which actually makes for a stronger higher revving motor because of the smaller mains, nothing to say you could not stroke a 350 up to a 400-421....we will probably see much more of this as the 400's suffer attrition....Pontiac motors are like owning land, they ain't making any more of it, so it is a dying breed.

PS: FYI Pontiac has never made a "Big Block", all the motors from 326-455 are the same physical dimensions, the only differences are the bores and casting thicknesses, thats why all pontiac heads after 64' are interchangeable, along with all accessories. And they will all swap in plug and play.


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## SPCMarty (Jul 29, 2011)

Would the edelbrock 72cc performer rpm heads be a good choice or is factory the way to go? I see edelbrock offers 87cc heads as well.


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## Instg8ter (Sep 28, 2010)

the Eddy 72's would be a good choice for the 350 and 400, but they will set you back a few grand themselves...


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## SPCMarty (Jul 29, 2011)

What is really the benefit of the edelbrock over factory if they're both 72cc

I should note that one real appealing thing about the Chevy 350s are the top end kits offered through Summit Racings catalog. The 410HP edelbrock kit in particular. I'm sure it's exaggerated some for advertising but it give y'all some insight to what I'm looking to achieve. I've seen zero kits for pontiac anything. 
Its a pretty penny but I'm well aware of it


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## Rukee (Feb 8, 2007)

With aluminum heads you can run a higher compression ratio without detonation because of the increased cooling capacity.


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## SPCMarty (Jul 29, 2011)

Ah I see. 
Would 71' 455 #66 heads benefit me much? 114ccs D port. Or #48 heads perhaps
I don't know if more cc is better or less is. I don't even know what my current heads are spec wise. All I really know about my engine is its 250hp with 2bb (given my bolt ons who knows) and has 8.5 compression ratio I think


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## russosborne (Dec 6, 2010)

I would recommend getting Rocky Rotella's pontiac engine book that came out last year. 
I come from the Ford world, and am still learning that I have a lot to learn about Pontiacs. The Pontiac engines are a completely different species from the others, including Chevy. 
His book has lots of information and also has several engine combinations listed with all the parts and power. 
Jim Hand's book is also considered a must read. A little older, but still worth it. 

Just in case you don't know, a 350 Chevy is not a bolt in to a Pontiac. Nothing in common except that they are both V8 engines really. Same with the other brands. 

Oh, in general the more cc's a head has the lower the compression will be compared to a smaller cc # head on the same short block. Unless I am totally confused by this point. 

hth some
Russ


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## Instg8ter (Sep 28, 2010)

you would need some that are 65-72cc to get you in the 9+:1 range which will be efficient combustion for todays pump gas.


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## SPCMarty (Jul 29, 2011)

The #48 heads list at 10.5 cr for the 69' 350. I like the sound of 10.5. 

I'm a ford truck person myself as well.


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## Instg8ter (Sep 28, 2010)

10.5 is too high for pump gas in a Pontiac, you will get detonation (spark knock) and it will shorten the life of the engine. You want to be between 9 and 9.5:1. You could make them work but you would have to order dished pistons. I sent you a sight with all the head cc's the 48's had a few variations from 62cc - 72cc check date and codes to verify which ones you have.


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## BearGFR (Aug 25, 2008)

Hey Marty, don't take this the wrong way as I mean it to be helpful --- but you are in serious need of some education before you make any decisions or spend any money.

First off, there's no such thing as a big block Pontiac. There's no such thing as a small block Pontiac. External dimensions of all Pontiac engines are the same, identical... as in if I were to pull a 455 and a 326 out of a couple of cars and put them on the floor in front of you, the only way you'd be able to tell the difference would be to start looking up codes from them.

Yeah, 350 chevys are cheap and plentiful. It takes no skill or brains at all to build one. However a 350 chevy on its best day can only dream of making even a fraction of the low end torque that you can get out of even a modestly built 350 Pontiac, let alone a 400 or larger. Horsepower is calculated from a combination of torque and rpm. Unless you're building a race-only car that's going to spend most of its life at the track, making lots of torque over a wide rpm range is infinitely more important than a big peak horsepower number. Torque is what you feel in the seat of your pants. Horespower is important for selling cars and for bench racing.

The only reason you care about cylinder head cc's is that the measurement is one of the figures that goes into determining overall static compression ratio. There are no inherent performance differences just because one head has chambers that are larger or smaller than a different head. What matters most about cylinder heads is overall air flow. That's where the power comes from - more air = more torque. 

It really would be a good idea for you to read the books that have been recommended. There's a lot of information in there that might help you in your planning and decision making. :cheers

Bear


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## SPCMarty (Jul 29, 2011)

No offense taken, I am terribly uneducated. I did know about the lack of a big and small block difference. The closest thing I had to a go fast car was an 03' Sentra which I sold the body (after spinning a rod bearing) and got my Lemans. My father has 70 Chevelle but his knowledge extends only as far as Chevy is concerned. 

I ask way too many questions some more than once, but I did order the book y'all recommended today off amazon... Along with a "objects in mirror are losing" sticker on an impulse


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## russosborne (Dec 6, 2010)

Nothing wrong with asking questions until you understand the answers.:lol:

I knew how to build a stroker 289 back in the 70's before that term was even around. But give me a Pontiac block and I am in trouble. But I am learning. slowly. very slowly. :rofl:

Russ


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## Icefan71 (Apr 7, 2011)

Marty, I bought a 72 Lemans last spring. I spent the rest of the spring and summer trying to get the motor to run. Then I tore the car apart. When the weather warms up, I'll start slowly cleaning it up and putting it back together. Over the winter, since I can't work on it, I've been doing a ton of research on Pontiac engines. Theres a few other Pontiac sites and lots of other stuff on the internet. I don't have the Rotella book, but I bought one written by Jim Hand, another Pontiac guru. I believe there is a member of this forum that helped write that book. Anyway, I'm like you. I'm not too experienced with Pontiacs, but I think I've learned a lot and now I have a better idea what I want to do with my car with the bugdet I have. So like these guys said before me, take your time and do lots of research. Learn about these Pontiacs and then you can figure out what you want. I know SBC's are a lot easier to work with. But I'm really diggin the fact that I have a car that isn't as common as the million other Chevelles and Camaros you see at the car shows. And from what I've seen and read, a Pontiac motor sure as hell can run with anything else.


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## NorwalkNugget (Aug 5, 2011)

Dude, I went from a blown 1971 350 to a 1973 rebuilt poncho 350 and have been SUPER happy. I got lucky for only like $300 off craiglist and it was 2 blocks away and the shop 4 blocks away.

Since doing that motor swap, now I have Hedman Headers and Flowmasters and TCI Streetfighter + Saturday Night Special converter. All I know is I am super proud of my car, it's torque, I can spin the tires at the light if I want and I can cruise up and down the highway no problems. Once in a while I get a loud pop during highway deaccceleartion but what's because of the headers/exhaust. 

I won't lie though, my secret goal is to someday get a hold of a clean 455 locally for under $1000 but if I somehow stumble across that then I'm going to completely redo the suspension to something that would really tighten up the car.


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## SPCMarty (Jul 29, 2011)

Are all 557 blocks weak? I read on another forum that the 557 blocks can handle N/A 450-500 horses. If that's the case then I'm more than alright with that.


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## BearGFR (Aug 25, 2008)

SPCMarty said:


> Are all 557 blocks weak? I read on another forum that the 557 blocks can handle N/A 450-500 horses. If that's the case then I'm more than alright with that.


They are weakER than the others that have more metal in the mains, but they're still viable for the power level you're talking about.

Bear


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## SPCMarty (Jul 29, 2011)

Well I'll be checking it out this Sunday. Said it was running pulled from a junk trans am.


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## SPCMarty (Jul 29, 2011)

With this 400 would 72cc heads be recommended as well?


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## Instg8ter (Sep 28, 2010)

here is the chart for comp...

Pontiac Cylinder Head and Engine Compression Ratio Chart

looks like your looking for heads in the 85-90cc range for stock iron heads. Those would be #64 or possibly #48 with the big valves , best way is to check and verify actual cc's as the varied from the factory a bit.


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## BearGFR (Aug 25, 2008)

SPCMarty said:


> With this 400 would 72cc heads be recommended as well?


It depends on several other measurements in the engine, and what pistons you use. On a 400 with standard bore size of 4.120 (hasn't been bored at all), standard factory gaskets (4.16 by .042", compressed), "usual" piston deck clearance (.020 "down"), and "usual" flat top pistons (6 cc's in the valve pockets), with 72cc heads you'd be at 9.935:1 static compression ratio. I think that's too high/risky in general. (With exactly the "right" cam and everything else "perfect", it -might- be possible to get away with it, but personally I wouldn't try it.). Run dished pistons with 11 cc's worth of dish volume, and you're at 9.473:1 which is much easier to work with. Change ANY of those "usual" measurements and it's going to affect compression ratio as well - that's why you have to have specific measurements on everything.

Bear


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## SPCMarty (Jul 29, 2011)

With the use of edelbrock aluminum heads wouldnt 9.9 cr be acceptavle


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## BearGFR (Aug 25, 2008)

SPCMarty said:


> With the use of edelbrock aluminum heads wouldnt 9.9 cr be acceptavle


Yes, with aluminum heads that would not only be acceptable, it would be recommended.

Bear


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## SPCMarty (Jul 29, 2011)

Well then perhaps it would be best for me to spend the extra dollar for 72cc edelbrock heads. 
The how to rebuild Pontiac v8 book arrived today so I'll give it thorough look through.


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## SPCMarty (Jul 29, 2011)

Reading the section about the 557 block a part stood out. It sounds like the main culprit of cracked blocks is the solid dowel pins exerting too much pressure. If I understood correctly they replaced dowels with roll pins to reduce that problem for 76-77' trans am 400s. This 400 I'm after came out of a trans am.


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## Koppster (Jul 27, 2008)

"400 Blocks produced after 1975 with the last 3 numbers #557 have an undercut support area from the main to the pan rail & I don't recommend for 400hp plus builds."

Pontiac Engine Block Casting Numbers


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## SPCMarty (Jul 29, 2011)

I read that part too. 
It sounds like that was pontiacs intent when switching to roll pins


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## SPCMarty (Jul 29, 2011)

Well picked up the engine. I included pics of all the codes on it except the 6X and 400 on the side. The 1097 and GM 5 I don't know what they mean. Came out of a 77 Grand Prix. 
Drove in snowstorm so i did what I could with an air compressor. 


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## Koppster (Jul 27, 2008)

Yeh...I read Rocky Rotella's book this morning and he devotes a page or so on the 557s. He talks about the roll pin being used in TA versions of the block only as a means to mitigate risk. He says the same as everyone else, fine for production engines and fine for 400 horsepower or less.


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## 68greengoat (Sep 15, 2005)

SPCMarty said:


> Well picked up the engine. I included pics of all the codes on it except the 6X and 400 on the side. The 1097 and GM 5 I don't know what they mean. Came out of a 77 Grand Prix.
> Drove in snowstorm so i did what I could with an air compressor.
> 
> 
> B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09



I'm thinking the 1097 is actually I097 - Sept. 9th 1977. Don't know about the GM5.


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## SPCMarty (Jul 29, 2011)

Are bell housings fairly universal across the Pontiac years? I have this now and the M20 but no bellhousig


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## Hot_Rod (Feb 10, 2011)

I think the reason a lot of people call them big blocks is, cause they're big blocks literally speaking, lol. These engines are huge compared to the common sbc. In fact they look bigger than a bbc, imo.


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## BearGFR (Aug 25, 2008)

Hot_Rod said:


> I think the reason a lot of people call them big blocks is, cause they're big blocks literally speaking, lol. These engines are huge compared to the common sbc. In fact they look bigger than a bbc, imo.


They're not though, Pontiacs are shorter lengthwise, and bore-spacing wise, than BBC's. They also have a much shorter crankshaft, which is why Pontiac cranks even in cast steel are more rigid and stronger than factory BBC cranks. In terms of overall dimensions, they're "in-between" the SBC and the BBC.

Popular American V8 Engine Dimensions

Bear


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## Hot_Rod (Feb 10, 2011)

Ah ok. Maybe people should call them IBB pontiacs. (in between block) haha.

Definitly their own breed for sure.


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## Pontiacpurebrred (Jun 22, 2011)

Hey man, welcome to the boards, I have followed a couple of your posts and I feel your pain. I know it's tough to find what you're looking for sometimes. 

First, I am in the KC area, I have a 400 block I will not be using, it's the "other" 77 400 block the XX block from the WS6 package. It is already .030 over and will need bored again but if you want it you can have it. I won't be using it. 

Second, and I apologize for not posting this sooner for you...and I guess for everyone. But you can search ALL of Craigslist using a site called Searchtempest.com. Just put in your zip code, how far out you're willing to search and what you're looking for. 

There are a lot of Pontiac folks up in Minnesota and Wisconsin. If you are patient (I am not a patient person either) you can find almost anything up there. 

Good luck with your build.


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## SPCMarty (Jul 29, 2011)

Pontiacpurebrred said:


> Hey man, welcome to the boards, I have followed a couple of your posts and I feel your pain. I know it's tough to find what you're looking for sometimes.
> 
> First, I am in the KC area, I have a 400 block I will not be using, it's the "other" 77 400 block the XX block from the WS6 package. It is already .030 over and will need bored again but if you want it you can have it. I won't be using it.
> 
> ...



What makes this XX different? I just bought a complete 400 as I showed above the 77 500557 block. A better block is always welcomed


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## Pontiacpurebrred (Jun 22, 2011)

I have this block that I am not using.

1978 400 220 HP WC M 8.1 402 6X 1-4 17058263 FB W72 Block Casting # XX481988

http://pontiacformula.free.fr/schema/W72pack.pdf

Sorry I said WS6 I meant W72 engine. 

It was the last "great" Pontiac 400 it's the same casting as an earlier (1968) 400 that was recast for the 77-79 Formula 400 6.6.


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## Pontiacpurebrred (Jun 22, 2011)

This is from High Performance Pontiac - 1967 Pontiac GTO - High Performance Pontiac Magazine

We knew that Pontiac introduced a series of revised 400ci-block castings during the mid-'70s that included casting Nos. 500557 and XX 481988. We also knew that Pontiac engineers eliminated the harmonic balancer from the nose of the crankshaft. I later spoke with a Pontiac engineer who confirmed that the elimination was a direct attempt at reducing overall vehicle weight to increase fuel economy, and that material was removed from both the block and crankshaft to lighten them, too. A detailed article entitled, "A Question of Balance," in the May '04 issue of HPP covers this very subject.

Having seen a number of disassembled No. 500557 engines, I am confident that when compared to previous 400ci castings, the No. 500557 definitely contains narrowed main saddles and oil pan rails, and-though not readily apparent-thinner cylinder walls. It's these features that make blocks of this vintage less desirable for high-horsepower builds. That doesn't, however, suggest that every Pontiac with a No. 500557 block under its hood can't be built to make power or that it is a ticking time bomb!

Through his continued research of the W72 Performance Package, hobbyist John Witzke determined that '77 T/A 6.6 engines received common No. 500557 400ci-block castings, while '78-'79 T/A 6.6 engines received casting No. 481988. The latter also had a large "XX" cast into it in several locations, including near the casting number on the rear of the block. Because of this, it is often referred to today as "XX 481988" or "481988 XX."

Not knowing a reason for the casting change or that any internal differences existed, we guessed that the No. XX 481988 was another "thinner" casting of the same era. What we didn't know at that time-and later figured out with key Pontiac engineering documents-was that some W72 engines were experiencing crankshaft failures, and while it may not have been directly related to the block casting itself, Pontiac revived the "better" No. 481988 casting last used in 1974 to eliminate the block as a variable.

By this time, Jim's book had already been released and was selling well. It wasn't long thereafter that the publisher informed him the initial run had sold out, and a second printing was scheduled. They gave him the opportunity to make minor changes, and he contacted his contributors, asking for any updates. I provided Jim with the "latest" known information we had on the No. XX 481988 block, and page 22 of the subsequent printing reflects this.

Paul Spotts later compared an XX 481988 casting to an earlier, vintage No. 481988 block and found that the two are virtually identical. All this information reveals that in 1978, Pontiac engineers felt safer using the "better" block for the T/A 6.6 engine and the No. 500557 in all non-T/A 6.6 400ci applications. Because the T/A 6.6 engines used in 1979 were machined and assembled during the '78 model year, they utilized the No. XX 481988 casting as well.

Having sorted through all of this, I can accurately state that the No. XX 481988 block is indeed a viable candidate for a performance build. While this statement might make the information in Jim's book appear incorrect, his book contains the most accurate information that was available at the time. I suspect that as research on all facets of our hobby continues and we uncover more information, we'll continue to see similar "mistakes" in the various books and articles that hobbyists currently use as reference material today.

Read more: 1967 Pontiac GTO - High Performance Pontiac Magazine


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## SPCMarty (Jul 29, 2011)

Anyone have thoughts on Lunati's Voodoo hydraulic cam kits for a 400? As being superior to edelbrock


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## Instg8ter (Sep 28, 2010)

Lunati has a much wider range of cams to suit your needs than Edelbrock. you want the cam profile that puts your power curve where you will need it most (street, track or somewhere in between)


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## BearGFR (Aug 25, 2008)

Instg8ter said:


> Lunati has a much wider range of cams to suit your needs than Edelbrock. you want the cam profile that puts your power curve where you will need it most (street, track or somewhere in between)


:agree Edelbrock is a well known "name", one that even inexperienced folk tend to associate with performance. Choosing the right cam however is more about the specific profile (lift, duration, lobe separation, lobe ramp rate) of the cam itself and the quality (accuracy) of machining and metallurgy than it is any one manufacturer.

Lunati is good. Comp is good. Crower is good. There are others. Some "names" from the past have gone out of business and have come back "under new ownership" as it were, and are actually either relative newcomers or of questionable quality. (Crane comes to mind in that regard)

Choosing a cam, start first with other decisions like how you plan to use the car, transmission type, rear gear, fuel type, need for accessories like power brakes, where the "normal" operating rpm range is going to be, how much you have to spend, etc. and that will tend to drive you towards some general characteristics. Once you have those, then check the various quality cam vendors to see who has profiles that are the best fit.

Bear


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## Instg8ter (Sep 28, 2010)

yep, cam is probably the single most important decision on the motor, needs to be dialed in to the range you will be operating the vehicle for you to be happy with your motors performance.


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## SPCMarty (Jul 29, 2011)

Well tentative plan after the block has been gone through at a shop, hoping I won't have to bore it out at all. 
Edelbrock 72cc heads, edelbrock performer rpm intake if it'll fit under the lemans' hood otherwise the edelbrock performer, edelbrock 750cfm carb. 3.42 rear end, Muncie M20

this one stood out to me
http://www.lunatipower.com/Product.aspx?id=2354&gid=297

This one was a recommendation on another Pontiac forum to another person seeking a 400cui cam
http://www.lunatipower.com/Product.aspx?id=2355&gid=297


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## Instg8ter (Sep 28, 2010)

i am running a lunati very similar to the first one and am very happy with it, nice idle, good vacuum.... heres what it sound like


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## SPCMarty (Jul 29, 2011)

Sounds excellent, I think a lunati would do quite well. 
So none of the listed parts are in the car yet, while the block is at the shop the 350 and trans will come out leaving me room to install the clutch assembly, haven't decided if the M20 should go in last or first or attached to the engine as it isinstalled


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## SPCMarty (Jul 29, 2011)

Anyone have thoughts on modifying the heads off the 71 350 that the car has now and placing them on the 400? Probably not as beneficial as the edelbrock heads. 


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## BearGFR (Aug 25, 2008)

Ain't no 'probably' to it - definitely not as good as the E-heads. However, also not as expensive. Which heads do you have now? (4 character date code and also the casting number off the tops of the center two exhause ports).

Bear


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## BearGFR (Aug 25, 2008)

SPCMarty said:


> Well tentative plan after the block has been gone through at a shop, hoping I won't have to bore it out at all.
> Edelbrock 72cc heads, edelbrock performer rpm intake if it'll fit under the lemans' hood otherwise the edelbrock performer, edelbrock 750cfm carb. 3.42 rear end, Muncie M20


What's your reasoning on picking the Edelbrock carb and RPM manifold?

Bear


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## SPCMarty (Jul 29, 2011)

It has #94 heads on the 350. And FYI the 400 has 6X heads likely 8 since it came from a grand prix just can't find the numeral stamping. It would be much cheaper. 

I already have the edelbrock carb on the 350 now along with performer intake. I figure the performer rpm would be a better match to heads and cam. 


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## BearGFR (Aug 25, 2008)

Here's a link to a photo that shows one of the places where you might find the head codes. I've seen heads with the "4" or the "8" in other places too, like on top of one of the end exhaust ports. Just look them over really good and you should be able to find it.

6x Head ID

Which cam are you planning on?

Bear


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## SPCMarty (Jul 29, 2011)

http://www.lunatipower.com/Product.aspx?id=2354&gid=297
I was thinking this Lunati 


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## SPCMarty (Jul 29, 2011)

Yup I looked there before using that photo


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## SPCMarty (Jul 29, 2011)

I don't know why I can't find this easily, what weight oil is used for the 77' 400s and 71' 350? 
I want to use Amsoil Z-rod high performace classic car oil and they offer 10w30 and 20w50


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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## SPCMarty (Jul 29, 2011)

It is a #8 on the head, just found it


B. Co. 1-22 Infantry 4th Infantry Division OIF 2008-09


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