Car Build help
 

Hey, guys. After bracket racing for several years, i'm working on building a stocker. The car is a 1976 firebird. My question is, what will be the most competitive, a 350, a 400, or a 455? Any help would be appreciated.

Re: Car Build help
 

The 350 and 400 combos are both good I would stay away from the 455 with the big combustion chamber.
Also an FYI all 3 motors have different versions of the 6X head with different combustion chamber volumes.

Re: Car Build help
 

Thanks, Bill. I checked out the NHRA blueprint guide and it tells which chamber head to use for each motor. Do these parts have to be dated 1976 or just meet the specs? Thanks again for the help

Re: Car Build help
 

Nope, the correct casting number is all that's necessary .

I'd run the 400. J, K, or L (K is the best bet, index-wise)
Let me know if you need any more help.

Re: Car Build help
 

I feel that both the 350 and 400 can be competitive which is why I too am building one for next year. How competitive you are will depend how much money you throw at it. There are a lot of fast cars in J,K,L, and M so if you want to run with the big dogs be prepared to buy all the best pieces. I'm projecting to have 28K in mine and that's starting with a car that doesn't need paint or interior work. I'm also trading some Q-Jets with a chassis shop in exchange for a chrome moly roll bar and sub-frame ties plus I wont have a lot in my own carburetor. But racecars always cost more than what you plan to spend. Good luck with yours and if you need a Q-Jet I can help. I have some of the fastest Pontiac Stocker customers in the country including Bill Edgeworth, Robbie Holmes, and David Horn. I can't advertise on this site but you can PM me. Danny

Re: Car Build help
 

So, can i use the smallest chamber 6x heads on a 400?

Re: Car Build help
 

No, for 1976 you must use the 6X-8 head (98cc) on the 400. The 350 can use the 91cc 6X-4 head.

Re: Car Build help
 

Go with the 400! p.s. the guys above ARE good Pontiac guys! ;)

Re: Car Build help
 

Hey, guys. Thanks again for all the help. I know you all have a lot of time invested in the knowledge that you have gained so i appreciate you sharing! I know i will have plenty of questions as the project progresses but all this research stuff is almost as fun as racing! Almost :)

Re: Car Build help
 

Thanks, Bill. At what RPM do you leave and shift at? Just wondering where these things run.