When I bougt my motor I was told that my compression was 225 across the board. I was satisfied knowing that my motor was realatively strong.

Today I did a compression test with my friends tool which hasw been used less than 10 times and i got 260 in cylinders 1, 2, and 4 (starting from drivers side moving to pass., and then 270 on 3).

I might have been able to get it up to 270 on all but I didn't want to push my luck. When I was doing the test I heard a poping clunk one time per cylinder(it happened four times) and we couldn't figure what it could have been, which obvouly scared me. I couldn't beleave that my motor was that strong. Is this possible? Maybe the shop never tested it/there compression tool was broke?

Is this an ok compression?

 

If it's not a JDM 11:1 motor that number is insanely high even for carbon buildup.

 

that is what I thought too, but I wasn't sure. Yes it a JDM motor-10:6:1, and I just put in new injectors that were running really rich, causing carbon buidup.

What should I do? Thanks guys

 

You might have to seafoam the engine w/ that much buildup, but first I'd go down to Chevron and get a bottle of techron or go to any local automotive place and run some Regane. See if that helps (keep in mind that w/ that much carbon buildup your car might have some problems running well while it's flushing all that junk), but that's a LOT of buildup.