Compression Ratio Question

[Cobra_Dusten]

Quick question, if a motor makes 10.4:1 compression with a 61Cc combustion chamber, what would be the compression ratio with a stock cobra head?

 

[SeventyMach1]

All I can tell you is that the GT40 heads are 65.6 cc. (some say 65.5 cc, though). I have no idea how to figure it out, though.

 

[nmcgrawj]

I would take a stab in the dark and say somewhere around 9.5:1 but i dont have any idea for sure

 

[Grn92LX]

If the gt40 heads have as big of a chamber as seventymach1 says, then you would be around 9.8-9.9:1.

 

[Cobra_Dusten]

hmmm, that is still a bit higher than i would want to run on a S/C motor...