Pontiac 400hp
xxGriffonxx
07-18-2009, 04:53 PM
All right so i have decided to sell the Olds 455 i have and get a Pontiac 400 To drop in my 66 LeMans. I have about 4-5 thousand to spend on the engine once i get it. Its a 72 400 "YS" Block with holly duel feed carb probably a 750, 7k3 heads. and a th400 transmission and i beleive everything else is stock. Im looking to get over 400 hp and closer to 500 ft lbs of torque.. first off im going to get a set of edelbrock rpm heads($1800) and a set of headers for it. How else should i go about achieving this goal in my price range.
MagicRat
07-21-2009, 04:07 PM
Click on MrPbody's profile and look up his previous posts. He has posted lots of tips on performance-building these engines over the years, as that is (in part) what he does for a living.
Also, he makes reference to an excellent book on building these engines. The name of the book escapes me right now, but is mentioned in several of his past posts.
Also, he makes reference to an excellent book on building these engines. The name of the book escapes me right now, but is mentioned in several of his past posts.
xxGriffonxx
07-21-2009, 07:40 PM
Allright, so ive been reading up and this is what ive come upon to reach my 400hp. Crane PowerMax hydraulic camshaft, Edelbrock Performer RPM heads, Edelbrock Performer RPM intake, Edelbrock Performer RPM750-cfm carb, Hooker headers, and Speed-Pro forged flat pistons, MSD Ignition system. Does this sound like a good build to start out on?
MrPbody
07-22-2009, 02:20 PM
Griff,
STOP!!!! DANGER! WARNING! You listed a bunch of brand x stuff that will be sure to turn a 400 Pontiac into a turd... "Chevy boys" will give you a list like that, then sit back and say "See? I told you they were pigs..." Properly done, Chevy guys HATE Pontiacs. Afterall, GTO didn't earn a reputation for LOSING.
The 7K3 heads must "go", this is true, but mainly because a good pair of headers won't bolt up (outboard bolt bosses aren't there). But there's no NEED for E-heads if all you're after is 1 HP per cube. The iron D-port heads can easily be modified for a lot less money than buying aluminum, and still reach that and much more. I would suggest some pre-'71 "large valve" heads, like 12s (a bit "rare"), 13s (not nearly as rare), 62s (all around us) or 16s ('68, not '70). Once porting begins, there is little or no difference between ANY of them. Chamber volume of those listed is "72", requiring a "dish" in the piston to get the compression "down".
The book MagicRat refers to is :"How to Build Max-performance Pontiac V8s" by Jim Hand, published by SA Designs. This is the only CURRENT book about the ol' Injun. The HO Racing books and Pete McCarthy's "Pontiac racers's Handbook" are good, but VERY "dated" (early '80s at best). We've learned a LOT in the last 25 years...
Crane is no longer in business, and their cams are one of the reasons. Very poor when compared to Comp or Crower, for modern grinds. The only Crane product we've used in Pontiacs in the last 10 years has been the XRi ignition system. SOMETIMES, their pushrods. Comp XE grinds are the best out there today, at least for a street engine. We've been selling a lot of the solid rollers of late, but they're pricey. Comp will grind up a solid flat-tappet that is VERY effective. If you use good valve train parts, "constant adjustment" of solids is a thing of the past. Comp also supplies the "drilled" lifters, that provide a constant stream of oil to the lobe.
Edelbrock Performer RPM is a good intake IF you have hood clearance. With the '66, you'll be okay. We usually recommend Torker II. Torque is a "given" with the Pontiac. Softening the low-end "grunt" with an open plenum intake makes for a better drag racer, anyway. Drivability is still very good.
Edelbrock carbs are absolutely worthless on a Pontiac. Either a well-done Q-Jet or a Holley is the way to go. We use AED Holleys. A 400 that will see 6,000 RPM needs a MINIMUM of a 750, but an 800 is better. Pontiacs LIKE "big" carbs. Cliff's high Performance in Ohio is the best source for a Q-Jet. He has Pontiacs in NHRA SS running low 9s with Q-Jet (Chevys came with Holleys, Pontiacs did not). John Angeles' '68 Firebird 400 runs 9.0s in C/SSA.
We use the Speed Pro L2262F-xxx in "stockers". It's very tough, but also very heavy, compared to modern high-level forgings. The relatively new Kieth Black FORGINGS (avoid the hyper-eutectic castings at all cost) are very good, and reasonably priced, while much lighter than the Speed Pros. For more money, there are MUCH better pistons out there.
Pontiacs are very sensitive to detonation, so compression ratio and octane are VERY important. 9.5:1 for iron heads, 10.2:1 for aluminum, assuming 93 octane gas. You MUST measure the chambers. "Published data" is "nominal" and not necessarily accurate.
Hookers are the best. They are also a bit "large", so some report ground clearance issues (usually on T/As, not A-bodies). Buy them uncoated and have them coated AFTER "fitment" with a thermal barrier. The ceramic coatings supplied by header companies won't hold up long. We use Thermal Tech in Hopewell, Virginia. Swain and Jet Hot also come to mind.
I could go on and on, but I think you get the idea. Get "the book" first. Once you begin to understand the rationale behind a good Pontiac "build", it will be safer to spend your money and get it right the FIRST time.
Our shop specializes in the Pontiac, but our slogan is "We don't care WHAT color you paint it, we'll build it!" To lend some credibility to my statements, I will say only this: The quickest and fastest Pontiac-powered car in the world is Dirty Bird, an alcohol F/C, making 2,000 HP, running 6.52 @ 213. The shortblock, valve train and overall design was done right here in the building... (:- We're VERY proud! Can't rev a Pontiac? Says WHO? Ours goes 9,000... 17 runs on it so far and no internal engine damage of any kind. Even the rod bearings are "happy"!
If you're near enough, the "TriPower Nationals" is at Norwalk Raceway Park in Ohio August 7-9. About 500 Pontiacs RACING, not including the show cars. If you really want to see what leading-edge Pontiacs are capable of, be there! Last year, the "bump" for the "Quick 16" was 8.0. One would never know there were so many 8 and 9 second Pontiac-powered cars in the whole world, much less within driving distance of Norwalk...
If you would like to, you're most welcome to e-mail me directly at:
mrpbody@centralvirginiamachine.com
I always supply good information, and you don't have to buy anything to get it!
Jim
STOP!!!! DANGER! WARNING! You listed a bunch of brand x stuff that will be sure to turn a 400 Pontiac into a turd... "Chevy boys" will give you a list like that, then sit back and say "See? I told you they were pigs..." Properly done, Chevy guys HATE Pontiacs. Afterall, GTO didn't earn a reputation for LOSING.
The 7K3 heads must "go", this is true, but mainly because a good pair of headers won't bolt up (outboard bolt bosses aren't there). But there's no NEED for E-heads if all you're after is 1 HP per cube. The iron D-port heads can easily be modified for a lot less money than buying aluminum, and still reach that and much more. I would suggest some pre-'71 "large valve" heads, like 12s (a bit "rare"), 13s (not nearly as rare), 62s (all around us) or 16s ('68, not '70). Once porting begins, there is little or no difference between ANY of them. Chamber volume of those listed is "72", requiring a "dish" in the piston to get the compression "down".
The book MagicRat refers to is :"How to Build Max-performance Pontiac V8s" by Jim Hand, published by SA Designs. This is the only CURRENT book about the ol' Injun. The HO Racing books and Pete McCarthy's "Pontiac racers's Handbook" are good, but VERY "dated" (early '80s at best). We've learned a LOT in the last 25 years...
Crane is no longer in business, and their cams are one of the reasons. Very poor when compared to Comp or Crower, for modern grinds. The only Crane product we've used in Pontiacs in the last 10 years has been the XRi ignition system. SOMETIMES, their pushrods. Comp XE grinds are the best out there today, at least for a street engine. We've been selling a lot of the solid rollers of late, but they're pricey. Comp will grind up a solid flat-tappet that is VERY effective. If you use good valve train parts, "constant adjustment" of solids is a thing of the past. Comp also supplies the "drilled" lifters, that provide a constant stream of oil to the lobe.
Edelbrock Performer RPM is a good intake IF you have hood clearance. With the '66, you'll be okay. We usually recommend Torker II. Torque is a "given" with the Pontiac. Softening the low-end "grunt" with an open plenum intake makes for a better drag racer, anyway. Drivability is still very good.
Edelbrock carbs are absolutely worthless on a Pontiac. Either a well-done Q-Jet or a Holley is the way to go. We use AED Holleys. A 400 that will see 6,000 RPM needs a MINIMUM of a 750, but an 800 is better. Pontiacs LIKE "big" carbs. Cliff's high Performance in Ohio is the best source for a Q-Jet. He has Pontiacs in NHRA SS running low 9s with Q-Jet (Chevys came with Holleys, Pontiacs did not). John Angeles' '68 Firebird 400 runs 9.0s in C/SSA.
We use the Speed Pro L2262F-xxx in "stockers". It's very tough, but also very heavy, compared to modern high-level forgings. The relatively new Kieth Black FORGINGS (avoid the hyper-eutectic castings at all cost) are very good, and reasonably priced, while much lighter than the Speed Pros. For more money, there are MUCH better pistons out there.
Pontiacs are very sensitive to detonation, so compression ratio and octane are VERY important. 9.5:1 for iron heads, 10.2:1 for aluminum, assuming 93 octane gas. You MUST measure the chambers. "Published data" is "nominal" and not necessarily accurate.
Hookers are the best. They are also a bit "large", so some report ground clearance issues (usually on T/As, not A-bodies). Buy them uncoated and have them coated AFTER "fitment" with a thermal barrier. The ceramic coatings supplied by header companies won't hold up long. We use Thermal Tech in Hopewell, Virginia. Swain and Jet Hot also come to mind.
I could go on and on, but I think you get the idea. Get "the book" first. Once you begin to understand the rationale behind a good Pontiac "build", it will be safer to spend your money and get it right the FIRST time.
Our shop specializes in the Pontiac, but our slogan is "We don't care WHAT color you paint it, we'll build it!" To lend some credibility to my statements, I will say only this: The quickest and fastest Pontiac-powered car in the world is Dirty Bird, an alcohol F/C, making 2,000 HP, running 6.52 @ 213. The shortblock, valve train and overall design was done right here in the building... (:- We're VERY proud! Can't rev a Pontiac? Says WHO? Ours goes 9,000... 17 runs on it so far and no internal engine damage of any kind. Even the rod bearings are "happy"!
If you're near enough, the "TriPower Nationals" is at Norwalk Raceway Park in Ohio August 7-9. About 500 Pontiacs RACING, not including the show cars. If you really want to see what leading-edge Pontiacs are capable of, be there! Last year, the "bump" for the "Quick 16" was 8.0. One would never know there were so many 8 and 9 second Pontiac-powered cars in the whole world, much less within driving distance of Norwalk...
If you would like to, you're most welcome to e-mail me directly at:
mrpbody@centralvirginiamachine.com
I always supply good information, and you don't have to buy anything to get it!
Jim
gburkett
07-30-2009, 05:54 PM
Mr P Body, I am sending you an E mail with a couple of questions about this.
Thanks
Thanks
xxGriffonxx
08-19-2009, 10:14 PM
Hey MrPBody i got "The Book" you recommended and i must say it is a great book.. almost everything i need to know about building a pontiac engine. was just wondering though will i need to get harder coil springs for my engine swap from the 326 to the 400 or are they reletively the same wight?
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