Guys
This is not an exact figure because the higher a compression ratio goes the more it is off but we used to say that for every 10cc of total head volume you removed your compresion ratio went up one. This is a close figure in the 9-1 to 12-1 range NOT EXACT but it is a good place to start if you don't want to do the exact math. To my knowledge late model six heads went from 60.32 to a max of 74.00 so using the above figure you can change your compression ratio about 1.4 by swaping heads.
Big Bill
Been there, Done that, Hope to live long enough to do it again.
Big Bill
I.I.# 4698
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