slant 6 head shave

roccodart440 said

Frank, using your math Charlie would have had to cut .147 off his head to get 39cc's. I believe you that advertised compression is less than what the factory states. WOuld be nice to know an exact formula though. As far as where I got my info, can't remember, some slant 6 forum? NOt this one.

WHat is the mechanical limiting factor as to how much you can cut off the head?

ALso how much would you have to cut off to get 10:1?

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How did you determine that I would have had to cut the head .147 to get 39 cc's? I never stated my original CC's. You need to know that before anything.

The factory head cc's is "spec'd" at 53.8 cc's, but most are actually larger. The head I used was an old "blue printed" stock eliminator head, which had been milled previously, to get 54 cc's. I had forgotten about the prior milling, and told the machinist to cut .100. This got the 39 cc's. If you do the math 54 cc's minus 39 cc's = 15 cc's, times .0066 = 99 thousanths. Close enough to .100 for me. I do not remember how much was removed in 1974 to get to 54 cc's.