I think I have a good feeling that my drain line is inefficient causing oil to backup and spit out of the turbine side. It usually does during cruising speed when compressor/turbine wheel spin is at minimum and/or when at WOT when oil pressure shoots to 50psi.
I have an oil restrictor in line by the way, I have installed it recently and it minimized the smoking but not much.
Here is the pic of the return line:
more close up how it sits:
here’s my idea of what might solve the problem:
Thanks for the future inputs, and NO I’m not buying a Full Race Traction Bar because of this problem
-compression of cylinders is 165 all across (cold)
-0.0625" restrictor in line
-headgasket is not leaking, no loss of coolant nor mixup of oil in radiator
-boost is set to 0.5bar
-"-3an" oil feed line
-"-10AN" return line
-boosted for about 4 months
-smokes on WOT and after cruising for a while going 60km/h, or when foot is off the gas pedal.
if you look at the direction of the 90 its pointing upward at one point, this can cause blockage for the drain, therefore oil backing up into the turbo and smoking, also the pressure builds up inside the center section and exiting through the compressor housing seals.