first and easiest thing to check is the oil return from turbo to pan.
make sure hose is 5/8" or larger
every inch is downhill no uphill or horizontal sections
pan is tapped above oil level
fitting at pan is horizontal and not tapped at an angle
line isnt kinked
also if you have a high out put oil pump you could be pumping too much oil into the turbo and it cant drain fast enough.
If your feed line is larger than 3an it will need a restrictor
Current: 04 Gt, sonic blue, 3.73s, 2.5" custom o/r exhaust, diablo tune, cai.
Sold: 90lx, stock short block & cam, TFS 170's, 1.72rr, typhoon intake, on3 kit 70mm, AOD, 4.10 gear, cobra 39s, C&L maf, stock tune, 11psi boost