hey guys does anyone no wat the cylinder compresion is meant to be in a rb30 turbo in psi ---------- Post added 29-03-12 at 22:20 ---------- im doing so many searches with so many different answers i dont no wat is right and wat is wrong

just check them all if they are al roughly the same they should be right if a couple vary dramatically you have a problem..

Quote: Originally Posted by 88wagon [View Post] just check them all if they are al roughly the same they should be right if a couple vary dramatically you have a problem.. I agree

Should be wiv in 10% of each other no major variance so if 100psi they should all be with in 10psi of each other , make sure battery is fully charged otherwise it'll crank slower by time get to last cyl giving doggy readings

Also depends on what cam you are running so what the guys are saying all ruff the same as each other all good if one is down abit on the others you have a problem what numbers did you get???

i got 120 psi across all it only varies about 4 to 5 psi across them all cam is standard i think in wat i could find in my seacrh people r getting 140 to 150 on standard turbo motors but thanks for the help guys

120 still ok n that's bugger differences it could have a decomp plate or mls which will change it , why you worried bout comp anyway is it burning oil blowing smoke or something

its has spat the dip stick a couple of times there is no decomp plate just the standard head gasket the head has been off before ,could it be valves or valve stem seals

So crank case pressure is the fault ok then things i,d after comp test would be breather system check the pcv valve . If wanna check valves do a wet compression test

pcv valve working ok im going to check if the rocker cover is blocked this arvo and do a wet test aswell see how that all goes it may just need a good freshen up

When it blu dip stick out was it missing at all ---------- Post added 30-03-12 at 14:20 ---------- Mine also has 120 across all 6 and mine never blows smoke or blows oil in catch can but i have big cam and mlsr headgasket but 120 is ok

It's possible my little bro rb25det was making 317rwkw only fault wiv that was crank case pressure under high boost at drift track would fill his catch can . When pulled engine apart you could see the too compression ring as edge of piston gone due to too much timing

nah was never missing i did just find that the fuel reg wasnt working thats fixed still havnt tried the wet test yet it doesnt blow any smoke