# Cam for 8.3:1 389



## mjc707 (May 28, 2015)

I have a 389 that I pulled from 65 gto to rear main and oil pan and clean up. I was thinking to put cam in it while I have it apart. 6x-8 heads cut to 92cc. Comp cams recommended High Energy Camshafts 51-232-3. I have read others using extreme energy cams for lower compression. Any thoughts on this cam or others you would suggest? basically stock setup. Motor had 112cc 4x heads and cam marked 540 233 which I have seen others ask about. I dont think its worth spending money on to get it measured out. Not looking for crazy HP just something to compliment the new 92cc heads. 3.42 rear axle and 4 speed muncie. Thanks in advance


----------



## bigD (Jul 21, 2016)

Voodoo 256 or 262--assuming your ring seal is good. 

Voodoo Hydraulic Flat Tappet Cam - Pontiac V8 256/262 - Lunati Power

Voodoo Hydraulic Flat Tappet Cam - Pontiac V8 262/268 - Lunati Power

And if you still have valve reliefs in the stock 389 location, be sure to check valve to piston clearance. The 6x head valves are at a different angle than the 389 head valves were. Therefore the reliefs are in a slightly different location.


----------



## mjc707 (May 28, 2015)

Valve reliefs are in stock locations. 4x heads were on it I am not sure if these are the same angle as the 6x. Thanks for the info. I will have to figure that out


----------



## geeteeohguy (Feb 2, 2008)

Helped a friend with his '65 389....stock heads but dished pistons. About 8.5 :1 max, probably a little less. 4 speed, 3.36 gear. Ran a Com Cams XE262 and a XE268, which is in it now, and it ran like a scalded cat with the 262 and still does with the 268, with a little more lope. He has a few years and a few thousand miles on it now, and it was a budget build that worked out very well.


----------



## bigD (Jul 21, 2016)

mjc707 said:


> Valve reliefs are in stock locations. 4x heads were on it I am not sure if these are the same angle as the 6x. Thanks for the info. I will have to figure that out


Yes, 4x & 6x heads have the same angle. But, again, the 389 reliefs are in a slightly different place than in '68-up 400 pistons. And, the valves in the big chamber heads may be slightly further from the pistons--don't know. If so, the same cam will put the valves closer to the pistons, when using the smaller chamber heads. Valve distance from the head surface may be the same, with just a bigger chamber. I suppose the difference(if any) could be measured, with accurate measuring equipment. 

Better to measure & check things BEFORE ordering parts.


"...Ran a Com Cams XE262 and a XE268..."

Most Pontiac engine builders do not recommend the XE cams. In fact, the CVMS guy is the only one I know of. For low compression builds most recommend the Voodoo cams, instead. They supposedly shut the valves more gently, making less "valve slap" noise, than the XE cams. 

No, I've never run any of these cams. Just passing on info. You can search the PY site, or ask them about the XE cams & get lots of opinions.


----------



## geeteeohguy (Feb 2, 2008)

The XE cams build a lot of cylinder pressure early, which works well with low compression applications. My friend's engine makes a ton of power from 1200 all the way past redline. That said, they are a poor choice for stock compression ratios because of the elevated cylinder pressures. Have also heard of the fast valve closure, but from what I've experienced, not an issue. your mileage may vary......


----------



## bigD (Jul 21, 2016)

If you wanna hear some feedback about XE cams, post the question on the PY forum. There are some very dissatisfied users.

And it's not just Pontiacs, the XE cams make noise in any engine, because of their aggressive lobe profiles. 

http://www.clubhotrod.com/ford-fe-big-block/47050-comp-cam-noise.html

http://www.chevelles.com/forums/18-engine/118413-comp-cams-xe-cams.html

http://www.camaros.net/forums/13-performance/67304-noisy-comp-xe-cam-valve-train-question.html

http://nastyz28.com/forum/threads/valve-train-noise-w-comp-cam-xe-268.76859/

The Voodoo cams have lobes which increase cyl pressure, without the noise. Not just my opinion. It's what LOTS of guys say, including many engine builders.


----------



## mjc707 (May 28, 2015)

Comp cams guy said he didnt recommend the XE but if I was to go with one to go with XE262 at the most. He also said I would get more vacuum since I have power brakes with the High energy. I sent in a cam recommendation form into Lunati a couple weeks ago and no response yet. I am not looking to build the whole motor at this time. I just couldnt see puting it back together the way it was


----------



## bigD (Jul 21, 2016)

The Voodoo 262 is similar to the XE 262 the CC guys mentioned, but without the noise, and has a 112 LSA, according to info I've read. 

Voodoo Hydraulic Flat Tappet Cam - Pontiac V8 262/268 - Lunati Power


----------



## mjc707 (May 28, 2015)

bigD I see what your saying about noise on XE cams. VooDoo cam looks like good option. I guess I need to figure out springs too. However the High energy from Comp supposedly does not have this noise. decisions decisions. I appreciate all the info. I am not sure what the difference in the 2 voodoo cams would be for my application


----------



## bigD (Jul 21, 2016)

mjc707 said:


> ... VooDoo cam looks like good option. I guess I need to figure out springs too. However the High energy from Comp supposedly does not have this noise. decisions decisions. I appreciate all the info. I am not sure what the difference in the 2 voodoo cams would be for my application


Many recommend the Crower 68404-16 springs, for the short valves, with 1.6 installed height. 

Crower 68404-16: Valve Springs Spring O.D.: 1.405" | JEGS

http://butlerperformance.com/i-2445...prings-cro-68404-16.html?ref=category:1234802

For longer valves, with a 1.7 installed height, some recommend the CC 995-16 springs.

http://www.ebay.com/itm/Comp-Cams-9...gs-/161242961513?_trksid=p2141725.m3641.l6368

http://www.jegs.com/i/COMP-Cams/249/995-16/10002/-1

http://butlerperformance.com/i-2445...-springs-cca-995-16.html?ref=category:1234802


"...However the High energy from Comp supposedly does not have this noise..."

I think those High Energy cams are single pattern & have a 110 LSA. Most Pontiac engine builders(but not all) say Pontiac street engines work better with dual pattern cams & at least a 112 LSA. 

http://www.compcams.com/Company/CC/cam-specs/cam-search-results.aspx?sc=70&sm=By+Engine+Family

The Dual Energy cams are dual pattern, but have a 110 LSA.


"...I am not sure what the difference in the 2 voodoo cams would be for my application."

The 256 would reach peak torque & hp at a lower rpm. Might also idle smoother, make a bit more vac, & get better gas mileage. The 262 would make it's peak torque & hp at a higher rpm. Might also have a slightly lumpy idle, and make a bit less vac. 

http://www.lunatipower.com/Product.aspx?id=1774&gid=287

http://www.lunatipower.com/Product.aspx?id=1775&gid=287


----------



## 1968gto421 (Mar 28, 2014)

Several people on the PY forum recommend the Crower 68404-16 springs as they allegedly fit in the Pontiac spring pockets and can handle a variety of lifts. Hope this helps.


----------



## geeteeohguy (Feb 2, 2008)

The single pattern Sig Erson Cam I installed in my '65 GTO's 389 36 years ago has an LSA of 108. Rough idle, 10" vacuum. Car runs like a scalded cat to this day. It is a 4 speed with mid-3 gears and headers. Tight LSA's can work, just depends on what your combo is and what you want. I agree that if you want more information than you can process on camshaft selection, the PY forums are the place to be! Good luck.


----------



## bigD (Jul 21, 2016)

"...Tight LSA's can work, just depends on what your combo is and what you want..."


Yeah, that's very true. A 4-speed guy, who wants a ruff idle, doesn't have vac power brakes, and don't care about gas mileage, can get by with a bigger single pattern & low LSA, just fine.

But, from all my reading, on several Pontiac forums, MOST(not all) street guys who drive their car a lot, want a smoother idle, lots of vac for power brakes, lots of low rpm torque, and good power to 5000rpm. Many rarely ever rev over 5000. For these guys, a good dual pattern, with less than .500 lift, between 215 & 230 degree intake duration @ .050 lift, & a 112-114 LSA, will give 'em exactly what they need. Obviously there are a lot of variables, such as: cubic inch, static compression, quench distance, rear gear, trans type, converter stall, etc. Then a big part of it depends on exactly what the individual wants from his car/engine. 

In general, a mild 350 engine will probably do better with around 215(or less) duration @ .050. A mild 400 might do better with around 220 dur @ .050. But, a 455 might do real good with around 230 @ .050. That's why so many choose an 041 clone, or a Crower 60243, for their mild 455 + engines. For those on a tight budget, I suppose a Summit 2802 cam & lifters, might be the cheapest decent 455 cam/lifter pkg. And, for the really low compression engines there are the small Voodoo cams.


----------



## extinctmake (Feb 8, 2011)

This is exactly what I'm looking for:

_But, from all my reading, on several Pontiac forums, MOST(not all) street guys who drive their car a lot, want a smoother idle, lots of vac for power brakes, lots of low rpm torque, and good power to 5000rpm. Many rarely ever rev over 5000. For these guys, a good dual pattern, with less than .500 lift, between 215 & 230 degree intake duration @ .050 lift, & a 112-114 LSA, will give 'em exactly what they need. Obviously there are a lot of variables, such as: cubic inch, static compression, quench distance, rear gear, trans type, converter stall, etc. Then a big part of it depends on exactly what the individual wants from his car/engine. 
_
My '65 GTO doesn't have power brakes, so vacuum isn't an issue. I have a Muncie 4-spd and 3.23 gears. As my engine is getting cleaned and magged, I am pondering many choices and anticipate some conflict with the machine shop over its suggestion of a roller cam for an engine that will not have all the sexy power adders. I am keeping it numbers matching with the stock small AFB carb and Delco distributor (recurved). I think I will spring for the H.O. exhaust manifolds. But by and large my engine will be 1965 down to the date coded Packard spark plug wires.

I like the idea of increased torque more than top end horse power. This engine will rarely see 5,000 rpm. I don't mind a little lope, but I don't need a window rattler. We'll just have to see what the man with the micrometer comes up with. Maybe that Summit cam bigD posted earlier could be an option. 


Getting a little nervous.....


----------



## mjc707 (May 28, 2015)

Thanks for all the info guys. I appreciate it. I guess now its decision time


----------

