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Discussion Starter #1
Me and father have a new project and were already coming up with ideas, hes not so savvy with internet but the one big flaw with this car is the crappy 6x-8 heads, one of the biggest performance things he wants to change.

For what it seems like the amount of money the big valve high comp stocker heads go for by the time you redo them and get the valvetrain all set and ready to go hes thinking might as well get aluminum heads with valvetrain ready to go for around a grand, not sure what heads hes talking about though, curious if this sounds right.

He wants it to be a strong running street/track car, im still kinda on the fence if it would be better to ditch the 350 for a 400 or 455 before we get too deep into it and be better off in the long run.
 

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I was going to put KRE or Edelbrock heads on my '67. but instead decided to cheap out and run 87cc iron heads. I ended up spending $1400 (this was 8 years ago) re-doing and upgrading my iron heads, as everything was worn out......I should have just sprung for the 72cc KRE's and have been done with it. More power, a TON less weight, excellent quality...no downside. Other than the buy in price....
 

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Yeah, not $1000 a set. OP your 350 is NOT a sbc. Before you spend a dime do some research on Pontiacs.
 

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Aluminum heads will be a waste of your dollars and disappointing at that - UNLESS you are going to build an all lightweight forged bottom end so the engine can spin upwards of 8,000 + RPM's, and of course the roller cam will have to be so radical that it won't be streetable.

Do a search on our forums to learn more about camshaft selection, engine builds, and head selection. Much of this has been covered here and good info is to be had by reading all you can.

NEVER, EVER, apply any small block chevy crap to a Pontiac engine. Its apples and oranges and if you or your machinist builds the engine thinking it is a chevy, you will be wondering why you spent so much money for so little performance returns.

Best bang for your buck is the 400 CI block, 1974 or earlier, and a 461 complete rotating bottom end assembly for $1,550 at Butler Pontiac Butler Performance - Pontiac Engine & Rotating Assembly Combinations - Featuring Eagle Pontiac Kits. You will find much material on this combo here on the site. Here is where you CAN use the aftermarket aluminum heads, but figure on about $2,400 for a set of PONTIAC heads, un-modifed out of the box. Then to really take advantage of the extra flow characteristics, you will want to select a roller cam set-up, probably another $1,000. Add in all the machine shop work, all your other match components and pieces and I'd say the build you are looking at will set you back near $7,500 - $8,000.

With this much HP & torque, don't expect the transmission or 10-bolt rear to hold up for too long, so budget for upgrades in both these areas as well as suspension improvements and front disc brakes to stop the car.

As suggested to other new comers to Pontiac's, the best thing to do is educate yourself about the engine and matching components that will work well together rather than hurt performance. Once you feel you have a good handle on this, then sit down and put together a build plan to include a budget or pricing. There are also a number of great books on building Pontiac engines and these give you the tried and true experience of what works. :thumbsup:
 

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All of the above is great advice. For more info, if you aren't already aware of it, try this site-- Pontiac - Street - PY Online Forums

It's the (Pontiac) Performance years forum with lots of good info like our GTO site.

This post is a good one to start with on building a Pontiac. -- 455 Super Duty build - PY Online Forums

On this forum, you always start on the bottom of the last page and work up the page, going from page 14 to page 1.

Good luck with your build and while Pontiac is more expensive than a SBC, the rewards (Torque!!) are greater.:smile3:
 

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Happened to remember that PontiacJim supplied us with this site which has lots of good info. (I believe the articles, 14 in all, were written by Jim Hand, a long time Pontiac racer and builder for decades.) Lots of interesting reading.

Building A Strong Street Machine | Dallas Area Pontiac Association

Your best sources for aluminum heads would be SD Performance and Butler Performance. They are very familiar with Pontiacs only (unlike Summit and Jegs whose tech info is primarily Chevy) and offer both unmodified heads and ported heads. Here are their sites--

SD Performance- Pontiac Performance Specialists

http://butlerperformance.com/
 

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Discussion Starter #8
Yea we know its not a chevy, he wants to keep it all pontiac and after talking to him hes wanting to build this 350 up a little bit then at a later date maybe a 400 build. The heads he was looking at were edelbrock heads... about all i know.

Ill have to do more reading and maybe print some stuff out for him, thanks for the help.
 

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E heads on a 350 Pontiac... a sure fire very expensive boondoggle. The small bore of the 350 is restrictive. Personally, am not even impressed with the results of box stock 87 cc E heads on a 462, have witnessed several resulting dyno runs in the 430-440hp range with rpm cam, rpm intake, and swapping on 780-850 dyno Holleys. Far from the 501hp claimed (on the "happy" Westech dyno) near 15 years ago with near identical build in CarCraft. Edelbrock sold a lot of 87 cc heads and RPM packages from that deal, have dealt with several individuals that took the hook.

As mentioned in your introductory post, consider studying & understanding the limits of the 350 Pontiac engine. Your Pontiac 350, being assembled by a prev owner with later 6x-8's is not a total bust, there are numerous core parts setting there. 6X-8's are far from "crappy" heads, the 6X's actually have the best short turn radius of all D port castings. For good part of the last 2 decades, 6X's have been a favorite of Pontiac engine builders for pump gas D port ported cast iron head 455-474 combinations. Consider picking up a local rebuildable 455 short block, they are out there! have the 455 short block built with good rods, forged pistons, block honed with a plate, assembled w the right cam. Melling 041 clone and rhoads lifters, for one, work. typical results with just comp VJ treated rebuilt 6x-8's on a 9.2-1 462 or 464, looking at 420-430hp/right under 500 ft lbs torque.

Desire more torque/hp, trade the near 100 cc chamber 6X-8's off for a pair of 6X-4's, 5C-4's, 5C-9's, or '70 model 15's. OR better yet...sell the core 6X-8's off to someone desiring to build a 9.2-1 stock head flow 462, and buy a pair of the above done...properly ported along w new guides, new stainless valve installed. the goal, is a slightly smaller chamber head, w/o paying stupid prices for '70 model 64 casting core heads as a start. Any of the above low 90cc to high 80 cc chamber heads rebuilt with new 1 piece stainless valves, new guides, and moderately ported to aprox 240-250 cfm (@28") on the intake side, 180-190 cfm on the exhaust, are going to work well. will need a bigger cam, 236-242 hft ground on a 112, has been a favorite. Not that hard with good tuning to break the 500 gross hp mark. Have a 451 ithat is a similar ported D port head build, right over 10-1 CR (main build difference is the offset ground "990" forged crank). Put a pencil to it during the winter as its been a collaboration of parts...have little over $3100 in the short block and another 2K spread between the 260 cfm heads, ported intake, carb spacer, modded Qjet, aircleaner, headers, HEI and wires. By again "buying right", if had to piece it together again could duplicate the entire combo with an armasteel or nodular iron 428 crank in the $4500 range.

Do your homework, it's easy to blow a lot of hard earned $$$$$ on a build.
 

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Discussion Starter #11
I printed out a shit ton of those articles for him and told him about butler, i need some info on something else considering for a fathers day present i found some heads for sale not too far away here is the info on them thinking about buying the first set. Since he has 6x-8s i think anything would be a improvement. Let me know if i should try to call and see if he still has them and try to buy, or if its not worth it.

Here is the add: 1968 400 Heads #15 75 cc small valve CR 10.50 Needs valve job, Have valves , what you to put it back together $100.00.......1970 350 80 cc heads complete will need valve Cr. 9.50 $50.00,,,To raise your compression
 
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