SR20 compression results... decent?

[Silverbullet]

from fan to firewall - 158, 160, 160, 157

good compression is 160 correct? Two of my cyl seem to be reading a little lower. How do i find out if its my head gasket or if its my piston rings that are going bad? And are these still ok to boost higher.. say 10psi?

[wootwoot]

the cylinders need to be within 15% of each other to be considered good. quit being stupid and worrying about the basically no difference

[HaLo]

yeah... i got 195-200 on all cylinders on the engine i got yesterday... unheard off. :p

[Andrew Bohan]

pfft i've hit 240psi on 2 of my cylinders.
of course i'm 11.2:1 though...

[HaLo]

yup... not 8.5:1
;)

[Silverbullet]

my motor seems to be running rough tho. you can espeically feel it under 3k rpms. It feels like and sounds like its only running on 3 clyinders and i've had multiple ppl ask me if that's the case. Thats why decided to to do the compression test. I recently ran this ITR. It pulled on me but it wasn't a total anhilation tho so i think its putting ou the power it hsould.. or atleast near it. One thing i can think of, my CAS dosn't have a cover so it might have a slight warpage or bend. Could that be the cause of the roughness? It really does sound like its only running on 3 clyinders tho. Anyone expirienced this issue here?

[Yoshi]

is your timing set correctly at 15 or so?

[BlackLimited]

The timing is on the dot for sure.

[Steeles]

well what we are telling you is its NOT a compression issue. move on to the next diagnosis. you dont know what the problem is, well you've eliminated one suspect. double check the timing now. that'll be another suspect. check the settings on the F-con. check spark plugs. etc etc.. see where Im going with this?

[Rick-95ZE]

It really does sound like its only running on 3 clyinders tho. Anyone expirienced this issue here?

I know that this post is a little over a month old, BUT! I don't see a conclusion to your problem....
I fixed a friends SR'd coupe that had the exact same problem.. and he tried everything that you had. I'll just say that it ended up being a wiring problem at the ECU that was affecting the fuel injector pulse to the #4.
so my advice is check fuel IF! you have already checked spark.

The wiring problem was do to a passenger kicking the ECU accidently.

[nissanrcer240]

Bad maf will make it run like shiat too, might want to check that out too

[WhiteGLX]

your comrpession is good, mine was as low as 130 on 2 cylinders......150, 130, 140, 130 that was over a month ago, i think it might be worse by now.....