Wierd smoke from SR.

[ZenkiDK]

Hi everyone, needed someone to sort of diagnose whats going on or point me in the right direction.

I have a 95 240sx with an SR20 swap. Mods include:
550cc injectors
Z32 MAF
Walbro 255
Full 3" exhaust
S15 turbo
FMIC
Enthalpy Tune

Recently, after every 5-10 minutes, when revving the motor, a puff of smoke comes off of the exhaust manifold area and at the same time from the exhaust tail pipe. The smoke is thick grey and smells like a lawn mower. Scared it might be the valve seals.

Any ideas or suggestions?

Thanks

Update 1/17/2018:

Got a tune.
Car is constantly smoking now and those puffs are still there at each rev.
Did a compression test and got 150psi across all 4 cylinders.
Spark plugs look normal, not black/rich. The outside area did have some oil, probably time to change the valve cover gasket.
I'm starting to think it might be the turbo???