16 replies to this topic

[gazza82]

So take 8cc of each calculation for flat-top pistons: a 12G202 has, I think, a 26.1cc chamber ... but check head as it may have been skimmed!

 

Total uncompressed volume = 249.66 + 26.1 + 8 + 1.4 + 0.6 = ~277.8cc

Total compressed volume = 26.1 + 8 + 1.4 + 0.6 = 28.1

 

Compression ratio = uncompressed volume / compressed volume 

C/R = 277.8 / 28.1 = 9.88

 

These are approximate figures and you will need to check the cc volume of the combustion chamber and replace the 26.1 in the above calculations with your combustion chamber volumes.

Edited by gazza82, 03 February 2015 - 08:26 AM.

[Shawbags]

_{Thanks for all the reply's great info , yes the engine number says it's a high compression engine so if that's the case would the head go strait on , in saying that I think the head could do with a slight skim because of some very minor marks or pitting , obviously I will know what pistons are fitted when I start to strip it down , Shawbags.}