Losing a lot of oil, smokes under boost.

[90 GSX]

I know what the usual causes of oil loss are, and I have checked them to the best of my ability:

-PCV is good, I also have a check valve on the PCV line
-I have a catch can
-Compression with my 2g pistons is 186-181-176-181, this was done cold
-The head is rebuilt with new valve seals
-I checked my turbo outlet for oil and it's dry, I'm also using an FP -4 restrictor

The car puts a cloud of blue smoke behind me only under boost, especially when it's loaded up in 3'rd or 4'th gear pulling hard. Also, ever since I installed my HX-35 (which is when these problems came about), my oil return line leaks where it goes into the oil pan. I am using flanges from theturbotrader.com and I made my own return with NPT barb fittings and aeroquip -10 oil hose. I am also using copper washers on the bolts and the thing is still leaking. It must be pressure pushing it out, although it doesn't leak anywhere else as far as I can tell. How can I figure out where to go from here? I'm sort of stumped. I sealed up the return as well as could be done. Everything on the car is done legit. The motor has about 20-30k miles on it as well as the head.

My plugs look pretty good. It's a little black around the rim but the electrodes are fairly clean. I think it's a combination of non-WOT tuning and running BR7ES (colder) plugs.

What do you think here? Am I missing something?

 

[Team Addiction]

turbo seals shot?? I just bought a GSX with the same issue escept this car has NO compression at all.
Claims he forgot to put in the outer seals when he attempted his own rebuild.
Hope that helps Im new to DSMs myself

 

[tbonitz301]

You pretty well went over everything that comes to mind. So im just going to take a stab at it, and say maybe you cracked an oil ring

 

[90 GSX]

You pretty well went over everything that comes to mind. So im just going to take a stab at it, and say maybe you cracked an oil ring

So I presume there is no way to check that right? How can I systematically solve this thing? I don't think it's a coincidence that it started doing this right when I put my new turbo on, but from what I can see, the turbo is not blowing oil.

 

[CHEVYTECH21]

under boost smoking would be turbo seals, check shaft play i just got screwed by a guy that sold me a car with a junk turbo, my bad for not checking the shaft play tho. and cheap valve stem seals or head gasket could be also.