Hey guys checked my compression on my 84mm LS today after a year of races and got some numbers ...

This is about 9:1 compression maybe a little lower due to some head work to the combustion chambers (still LS head) ... SO the lowest maybe 8.9:1 or so but lets leave it at 9:1.

Ok from the dizzy

cyl 4 148
cyl 3 150
cyl 2 146
cyl 1 151

All done full throttle with all the spark plugs removed to check for any head-gasket problems. Also done with a cold motor.

I can not seem to find anywhere even what a B20B with 8.8:1 compression should be to even have something to compare so I am stuck asking you guys for some help.

How can I figure out what it should be or does any one happen to know about what I should be getting... I think B20's are about 150 or so but like I said I cant find it anywhere online anymore.

Any help would be great thanks guys

 

8:1-8.5:1 compression: 150-170 psi per cylinder
8.5:1~9.5:1 compression: 170-210 psi per cylinder
9.5:1~11:1 compression: 210-275 psi per cylinder
11:1+ compression: 250+ per cylinder (highly depends on cams being used)

evans-tuning.com

 

thanks a lot man

Now I have to factor in weither or not my cams lowered my number or if the rings never sealed hahhaha