What are good compression numbers for a stock H23? Need to know for a compression test. Also, for H22's, if ya know(friend is also doing one)

 

i hit 207 for the low and 212 was the highest
do a wet and a dry test.. they shouldnt vary more than 15psi or so..

 

Stupid question. Whats a wet and dry test?

Thanks

 

If you suspect leaking piston rings put a small amount of oil down the cylinder, it will seal the rings enough to perform a compression test. If the #'s improve suspect bad rings. If they dont, suspect head gasket or, more likely, valves.

 

around 200 - 210 is good. Make sure the motor is hot. Numbers should be within 10% of each other.

 

Thanx for the info. If I suspect valves, how would I go about doing a leak down test? Or is it even necessary? Also, how much oil for a wet comp. test, and will it crank afterwards?



[Modified by LudeyKrus, 2:44 PM 11/5/2002]

 

Well before I went turbo I turned out..
150 160 150 150 (dry test)
trouble free for over a year a 7-9 psi daily

 

eww low numbers man.. leak down is u take an air compressor and fill the cylinder up with air pressure through the spark plug hole. (yea its a special tool most compression guages you just disconnet and hook up air hose to it...) then let it sit for a few and put the guage back on it. basicly its not really gonna tell u if its the valves or the piston rings..

 

For your friend, a JDM H22A (mine) did 255 250 255 255 (dry test) , USDM H22A should be lower.

 

Are you saying that the 7-9psi eventually killed your motor?
I want to put about 7-9 psi in a relativly stock H23 with about 8.5-9:1 CR, and I am wondering if it will eventually kill the block...

 

I just did mine today 99' USDM H22a4 and the numbers were 240 across the board no more than three psi diffrence. Is this what everyone else is getting for 5th gen dry tests on a warm motor.?