Smoke coming out of breather hole Any ideas????

[japarossa]

Ok I swapped out my motor a few months ago to a K24a2 with boost. Car was running great up until today, I was doing a 2500rpm-6000rpm pull datalogging it and everything looked good, I pushed in the clutch and pulled the car over and it was dead.
I tried to restart it and was able to start it while giving it a bit of gas but now I have smoke coming out of the breather hole on the valve cover.
I thought it was the pvc valve (best case scenario) but it wasn't. I have pulled the valve cover and everything looked good and tight. I pulled the plugs and they all looked good. I checked the oil and it is still the color of new oil. Drained the coolant and its not contaminated with oil. So I got down to doing a compression test and this is where I found a problem cylinder #1-100psi #2-180 psi #3-90psi #4-90psi. Now these cylinders all hold pressure for 30 minutes each. Any ideas what it is? I know its gonna be bad but how bad is the question. I'm pulling the motor right now so I should be able to get the head off in the next few days to take a better look.
I have had a tuner look at the datalogs and he didn't see anything wrong even at the time when it happened. Any Idea's?

[talonXracer]

I would say the rings/cylinders are worn, bottom on the exhaust side and middle-ish on the intake side of each of the bad cylinder walls.

[oneglory]

damn it doug. let me answer a damn engine question for once.

[japarossa]

Well thats not to bad if thats all it is. Just seems strange that it went from working perfect with good compression to smoke billowing out of the breather hole in just a few minutes of driving. Oh well I guess no matter what the problem is its a reason to build it for boost this time around.
Thanks Talon I figured you would have a pretty good idea what it was.

[AKEP]

I would say the rings/cylinders are worn, bottom on the exhaust side and middle-ish on the intake side of each of the bad cylinder walls.

why does this happen?