75 t/a

unfortunetly my questions are similiar to most other guys looking to make 400 hp from a 400, but my dilema is how to go about it. the car runs but doesnt like to be turned off, continuing to sputter well after im gone. so i want to get the carb straightened out, to drive it now. in the same sense i want to purchase what i can to get to the 400 mark one part ata time.will a new carb or rebuilt work for stock and then need tuned again for mods? i purchased the exhaust, a flowmaster american thunder series header back. the headers are also in question. will 200 $ headers suffice or go for tuned 500$? an msd super hei kit is in the works along with an rpm performer manifold. "ill deal with shaker clearance later" with wires and plugs of course. and a billet timing chain and high volume water pump. i have the cash for these items now and plan on heads soon. followed by internals whenever i get the cash. am i headed in the right direction? should a, or could a cam be used now with the stock internals, stock heads? any suggestions where the money should go first?

Hi I am not a pontiac expert Mrpbody should be along soon and he's the guy with all the answers, but I know how it sux waiting so I will try and help if I'm wrong Pbody will correct me and I will have learned something :P.
Yes you can put a new carb on it now, IMO edelbrocks are always good to have as a starter carb and for when your doing engine builds, I find there a nice carb to throw on and engine to fire it up get the kinks worked out before you throw on an expensive high performance carb.
To me it seems your going in generally the right direction as far as the came goes what heads are you running, and what cam are you planning on using?
IMO a new cam and head work go hand in hand new rockers ect.

Don't forget about a new Torque converter as well.
If you have the money a good thing to do would be call around to you local automotive machine shops talk with the guys and find the one that is the most Pontiac savvy make sure it's Pontiac knowledge and not sbc. talk to him and have him help you map out a build to your taste.

Maxdad,

First, let me welcome you to the upper echelon of GM performance. You'll be getting lots of "advice" from all the non-believers around you. Ignore it. Get Jim Hand's "How to Build Max-performance Pontiac V8s" published by SA Designs. This is the only CURRENT study of the ol' "Injun". Lots of good information and answers to many of your questions as far as the "quirks" of the Pontiac, are in there.

The exhaust system you bought... Is that a 2 1/2" system? Hope so. 3" is too big. Hooker headers are hands-down, the best. The "Super Comp" will make more power than any other "out of the box" header from any manufacturer. If ground clearance is an issue (you want more), Mad Dog is the header of choice. You need a 1 3/4" primary tube, 30" long, with a 10-11" long 3" collector. Whether or not you "need" the more expensive headers is strictly up to you. Which is more important to you? Quality/power production? Or price? When you DO buy headers, buy them "uncoated" and send them to a real "coating shop" for a thermal barrier. The ceramic coatings applied by header companies doesn't "live" and the headers will rust out relatively quickly. We use Thermal Tech in Hopewell, Virginia. Jet Hot and Swain are two others that come to mind.

Making 400 HP on 93 octane gas is no big deal with a 400 Pontiac. Good cam selection, the right intake and exhaust, along with some mild port work and you're "there". Static compression should be kept under 9.3:1 with iron heads. The 5Cs (head casting) that were original on your '75 are actually pretty decent. Mill .060" from them, port the intake and exhaust according to the chapter in Jim's book, and you're nearly there. We (CVMS) use Comp's XE grinds, pretty much exclusively in our pump-gas Pontiacs. Don't be "shy" about solid lifters. All the talk of constant maintainence is just that. Talk. With modern valve train parts, solids are VERY reliable in street applications. They ALWAYS make more power than an equal hydraulic cam, as well.

I highly recommend AGAINST using an Edelbrock carb. We've seen nothing but "grief" from them on any application that doesn't include a 350 Chevy. The original Q-Jet, properly rebuilt, is FAR superior (may be one of the best carbs ever by anyone). If using an aftermarket intake like Torker II or Performer RPM, an AED Holley is our choice. For the 400, the "750HO" is adequate. If you stick with the original Q-Jet intake (good flow regardless of the EGR provision), the Q-Jet is the carb. Unlike other engines, the Pontiac's "stock" intakes are very good. The "Ram Air" or "HO" exhaust manifolds are also very good (better than "cheap" headers).

A couple of VERY important points to consider when building a Pontiac V8 for performance. First, "tune" to the engine's "strength". That is, make it a low-rev performer. Pontiacs make good power right off idle and can rev to 6,000 without worries, especially if you replace the connecting rods with good forgings (HIGHLY recommended regardless of "build"). No need for "monster" cams that can't make power under 3,500. Second, this is NOT a Chevy. Using the same approach as when building a small block will result in a Pontiac that is short-lived AND a "pig". As said before, do solid research and ignore the "buzzing" in your ear... Your Chevy "buddies" will HATE your Pontiac if you "follow instructions". They'll laugh at it if you do it their way and it "pops" (it will...).

Always remember: "GTO didn't get a reputation for LOSING..."

Build a solid short block. From there, you can make changes in the future to improve power, without risking damage to the most expensive parts. If I can be of further assistance, just say the word!

Jim

I highly recommend AGAINST using an Edelbrock carb. We've seen nothing but "grief" from them on any application that doesn't include a 350 Chevy.
ok this makes sense I've only used them on sbc builds then shelved them as soon as they were tuned and ready for a holly.