s14rb20 compression test?

[lexrob]

I hate to ask this but im going to look at a 240 with a rb20 in it and want to do a compression test to give idea of health. How would i disable the fuel system.... unplug pump.. unplug ecu.. or pull same fuse when doing a reg. compression test with stock motor.

[legit240sx]

ummm you are talking about the old pull the plugs out, put in a pressure gauge, and turn over at WOT for five seconds right??? because if it is its exactly what i just said and nothing more....easy as pulling coil packs and spark plugs...

[Joe]

disable the fuel and spark. dont just remove the coilpacks and go to town.

[lexrob]

so just pull fuses and good to go same as stock .. thanks hopefully its good !!!! guy ran it for 2 years... got it from jhot?? I read that stock comp number should be between 150-171 can someone confirm.

Im driving three hours to check it out anything else i should watch out for.

[Carl H]

pop the oil cap, should smell like fresh oil and not burnt oil.

disconnect the cam angle sensor, this will prevent the ecu from firing the injectors or coils and will allow you to perform a comp test easily.be sure the engine is fully warmed up and the test is done with ALL spark plugs out and at wide open throttle.failing for the rb20 comp wise is 125psi, new compression is 175psi...a 3psi variance between cylinders is acceptable.