Im current owner of 01-248 an this would be my first time posting here on HT. Had a miss shift last night into 5th. Compression test as of this morning reads #1 cylinder 240psi, #2 cylinder 255psi, #3 cylinder 265psi, #4 cylinder 255psi. So the question is did i bend a valve and do i need to take it to a shop to get looked at or am i over reacting? I have JDM ITR pistons and a Mugen HG so im assuming the compression ratio is around 11.5. I also noticed a little oil around the threads of the #1 cylinder spark plug. All input is greatly appreciated.

Me worring about my R

 

you also should perform a leak down test. Once you have both done you can go from there. With a comp. test it's more about similarity across the board.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SikITR01-248 &raquo;</TD></TR><TR><TD CLASS="quote">Im current owner of 01-248 an this would be my first time posting here on HT. Had a miss shift last night into 5th. Compression test as of this morning reads #1 cylinder 240psi, #2 cylinder 255psi, #3 cylinder 265psi, #4 cylinder 255psi. So the question is did i bend a valve and do i need to take it to a shop to get looked at or am i over reacting? I have JDM ITR pistons and a Mugen HG so im assuming the compression ratio is around 11.5. I also noticed a little oil around the threads of the #1 cylinder spark plug. All input is greatly appreciated.

Me worring about my R </TD></TR></TABLE>

Those compression numbers are actually not that bad, a 25psi spread (and #3 is like 10 psi higher than the other two), could be due to test error even. When you say misshift into 5th? Do you mean 4th-3rd? or 2nd-5th? AFAIK, there is no misshifting into 5th... atleast not the damaging money shift... just the bog-like-a-newb shift

 

yeah those numbers dont look that bad. It could definitely be a lot worse when it comes to mis-shifting.

the oil on the spark plug threads could just be the O ring gasket on the valve cover leaking slightly. Id be more worried about oil on the electrodes, or smoking from the exhaust.

you could probably do a valve adjustment and go from there. Maybe do a leakdown to see if you losing compression anywhere. But I wouldnt be too worried.

 

Im planning on buying a leakdown tester later today and doing that. The miss shift was 4th-3rd sorry for the retarded information. I caught it as quickly as possible and remember the needle being about 9300. For the valve adjustment dont i need a special tool? I remember reading a post about a guy putting a 90 dregree bend at the end of the wrench to get it down to the valve. Reading your replies is starting to calm my nerves.

 

Like they said, the number aren't bad at all but you should leak down test it just to be safe.

 

snap on sells a "special tool" for valve adjustments, costs like $40. Or you can bend a wrench and use a flat head screwdriver but its a little more of a pain in the *** without the "proper" tool.

 

Your compression reading is fine. I doubt you bent anything. I've over revved to 10k + on an ITR valvetrain without hurting anything measurable.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SikITR01-248 &raquo;</TD></TR><TR><TD CLASS="quote"> Reading your replies is starting to calm my nerves.
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Good, b/c your #'s dont look bad at all! YOu wont be able to tell a difference with those variances anyways. I once bent some valves and did a compresion test finding my #'s to be 210, 150, 65, 30 (not in that order) and couldn't notice much of a difference. Its b/c the valves are so light and flexible that at high RPMs they are still seating correctly. Its not usually until your sitting at idle that you notice the fluxuations in RPMs, or even your car stalling. No worries...sounds like a valve adjustment could fix everything for you

 

Your numbers look fine - don't lose any sleep over it.