Ok so i just bought my new GSR and when i did the compression test i got 190/170/120/180!!!!! i dont know exactly what it could be! the car runs and drives ok but i knew it didnt feel as powerful as it should for some reason. I just found out, after i bought it, that it used to be boosted. Im thinking it could be piston rings or maybe a bent valve from reving to high, i dont have any experience in tearing apart my internals so im kinda worried.

Does anyone know what it could be? Please Help and give any insights you might have!!!!!!!!

Im no expert but i'll agree with you on the piston ring going out on that cylinder...

With many boosted Honda motors that ive seen, the rings gland crack, and thuse making lose compression. If thats not the case the rings are gone and need replacement.

Shouldnt all my numbers be in the 200s? the one cylinder def has an issue, but arent the others suposed to be higher as well?

180-190 is normal from what i have seen. Regardless of the numbers, you would have to tear down your motor and figure out what it is. I still think the rings are gone, but to be really sure an engine tear down will need to be done.

leakdown test is in order.. but i'ma guess it needs a new valvejob.

How do you do a leakdown test and what would that mean if it fails? Anyone know if there is a how to walktrough?

can test for both problem without braking the motor down take and remove the spark plug in the cylinder that has 120 you will want to use an oil can spray oil on the cylinder wall put the copression tester back in turn the motor over to test the cylinder if it builds up compression over the 120 mark you have bad rings if it stays the same 120 you have a bad valve keep us posted

You will be fine..my ls compression was 90/180/165/170....and i been driving it like that since may wen i first found out about it...yeah you might not have all the power you could..but its nothing i would immediately tear the motor apart about...