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Revolver Ocelot
06-30-2005, 02:23 AM
Do these compression numbers sound good to you guys? 130,145,132,135,130,128. They are all pretty close except the 145 and 128. These numbers are all for an Rb25.

Father Time
06-30-2005, 05:38 AM
dont know for sure what rb service limits are ( ~150's?) but those are low numbers.

prophet_19
06-30-2005, 09:59 PM
it says it in the FSM

sdtouge
06-30-2005, 10:47 PM
doesnt sound too good. not terrible but unless your rebuilding it i would stay away from it.

check the skyline factory servie manual and see what the specs are for high/low and see what the max diff% between cylinders is.

nismo101
07-01-2005, 09:40 AM
Do these compression numbers sound good to you guys? 130,145,132,135,130,128. They are all pretty close except the 145 and 128. These numbers are all for an Rb25.

did you do it with the engine warm? Compression numbers go up with warm parts.

I bought a FWD SR20DE for my old sentra SE-R, I did compression check right when I got the engine, it was pitiful. One cylinder was down 50 psi! the others were all low. This engine may had been sitting in a JDM wrecking yard for a few years, so there was probably some oxidation in the cylinder walls.

After getting the engine running and driving it for a month, I did another compression check, with the engine warm, they all came out to 210psi dead even in every cylinder, and it stayed that way until I sold the car.

ledzeppelin240
07-01-2005, 04:28 PM
There can be a 20% difference between cylinders generally speaking. Did you have the throttle plate blocked open, if not you will get lower numbers...