Question out of left field..ZX11, ZRX1100 pistons

[Roger P.]

Not to be a smartass, but 299.4 + 33 = 332.4

Divided by 33 = 10.0727, so we were both off.

That sounds like a more useable CR.

[GregT]

I plead old age related dyslexia....
That's still higher than reality because of the way the chamber volumes were calculated....but only maybe point four of a ratio at a guess.
Only real way to be sure is to mock it up and measure head volume at TDC then adjust as necessary.

[still_bluenoser]

Subscribed, I really hope someone follows through with this.

[jimb12]

Your math for the CR is slightly off. Conventionally, it's total cylinder volume (incl combustion chamber) divided by chamber volume.

Actually the compression ratio is volume at BDC divided by volume at TDC. Besides the combustion chamber, you also need to account for the head gasket, deck clearance, and piston dome/relief volumes when at TDC.