Originally Posted by woj's72lemans
okay so i just bought a 76 pontiac 400 engine that i am aiming to build up for power that will eventually be put into my 72 lemans. now as far as thi motor i heard it is a slug but can be built up. i am looking to bore it .30 over, cam it, headers, edelbrock performer or air gap manifod, and i am just unsure of the ebst way to achieve my goal. please help me ith any information, tips, advice, or part suggestions thank you
The late model year '75 and all of '76 Pontiac blocks with casting #500557 are NOT a good choice for any kind of build up. As a cost saving measure, the factory cast them thin in the main webbing area and they are prone to breakage, especially when used in a build up application. Any other casting # 400 block is better suited to any kind of hopping up. The casting number can be found on the lip behind the passanger side head. See the attachement.