The builder says we should be around 10.3:1 CR with the 75 cc heads. He is more concerned about valve clearance though. So that’s why I was thinking maybe go with the 80cc, and then if we need to have them milled down to where we want, that would be good. Thoughts on that idea?

Also, what about the roller rockers vs stamped steel, or any opinion on the Mancini version of the Harlan rockers? Thanks.

1971 Cuda, 440 custom-build