mrm95

iTrader: (1)

So when i first bought my IX RS 2 years ago i found out shortly after that it had bad compression in 2 cylinders (70,100,140,140) then after performing a leak down test it showed the exhaust valves were leaking. Once i got the head rebuilt and got the car tuned it always made amazing numbers after that (340whp on 91 oct) then once i switched to E85 it has made 413/425 and this was dynoed less than 1k mile ago. Ive been on E85 since sept of 2013 and have always made expected or even better than expected numbers. Well i just compression tested it again trying to figure out a somewhat rough idle that the car has always had (some on here say its normal) however when i compression tested it tonight i got 90-120-120-120. So my 2 cylinders that were good initially at 140 are now at 120.. ive driven only 10k miles since then after the head rebuild and ive always changed the oil at 2-3k miles, etc. The car has always performed well and made great numbers.. any ideas? a 30 psi variation kind of scares me... also, i added a small cap of oil to the first cylinder and the compression went up about 10 psi to 100 psi.

STLEVOIX

iTrader: (17)

Can you do another leakdown test?

mrm95

iTrader: (1)

Im going to give that a shot.. Because i figured pouring oil into the cylinder was gonna make the compression shoot up more than just 10 psi. Also from what ive seen and heard, 1 low cylinder is generally something other than the rings.

mrm95

iTrader: (1)

I figured if it were the rings they would all be equally low