by pc » Wed Mar 01, 2006 5:48 pm
What you have measured is the 'compression' which is not the 'compression ratio'.
Pull the head off and measure all the empty space in the cylinder/head/headgasket etc. Then work out the ratio of that space from TDC to BDC.
If its a stock engine then it will be a stock compression ratio... which is reasonably well publicised and easy to find... about 9.4:1 for a bluetop (i think)
AFAIK there is no way of working out compression ratio from the compression test as all engines are different and there is no direct correlation between the two.
red car
1/4 mile - 14.683s @ 91.83mph
Manfield - 1:24s
Taupo - Track1 1:53s (road tyres) - Track2 1:22s - Track3 48s (with esses) - Track4 1:58s