Needing a good recipe for Pontiac 400 pre 75 yr modle

[Rocky66]

Hi All, I'm needing some good recipes to building a low budget build for a Pontiac 400 pre 75 year. This build has to be done the old school way using factory cast iron parts such as block, heads, intake etc. This build needs to produce 450+ HP. The block can be bored .30 over. Any info on achieving this goal would be greatly appreciated. This beast will be going in my 67 C10 shorted with a TH350 built. Please help me prove to these younger generation of kids who says it's not possible. I'm old school all the way. Age 60. Thanks guy's

[m91196]

Pretty easy to hit, 500 is easy if you’re willing to stroke it. Best bet is one of the Pontiac forums and Butler/Kaufmans sites and the FAST social media sites.

[68Formula]

How's your porting skills? The factory heads are pretty limited, but can be made to flow with the correct work. That's going to be your biggest bottleneck.



I have a set of unused freshly rebuilt iron, milled, screwed in studs, and professionally ported by SD Performance (top Pontiac-specialist porters) I'm looking to sell (can provide the flow sheet they came with). Milled to 90cc since they were planned for a 10:1 455. They're great, because SD focuses on improving the flow, while minimizing the amount of runner volume increase, so they not only flow great on a bench, but high port velocity for streetability. I think if you zero-deck the dock, with flat stop pistons it'd still put in you close to 9:1 compression on a 400. Also have a ported Edelbrock RPM intake to go with it. With a mild cam on your 400, that top end package will easily meet your target and save a lot work. More like 500hp if you stroke it to 461.