I havent been having good luck with turbos,i am pushing oil past the seals. i narrowed it down to oil pressure, my drain is perfect now, i even put a clear hose on when i first started the car with my new turbo and watched the oil flow smoothly.

what oil restrictor should i use? its a generic t3 t4. t04e turbo.

I have a -4 feed line, and i think the restrictor is .065 or .080.

i recently ordered a -3 oil feed and a .065 restrictor from go-auto works. this line is quite a bit smaller than a -4

what do you reccomend? thanks. its on a b20b

 

I dont have any restrictor and my oil pressure is not super high on it 65psi maybe. I dont see smoke.

whats your oil pressure at cold start?

 

this has to be the oldest known issue to man! lol I believe I have figured it out.. heres my story ..
So I got a brand new Garret GT4088R, practically my first BB turbo and right off the bat after a few minutes of running clouds of oil smoke.. not good!! take it off and send it to Precision which assured me the turbo was in great shape just needed to "break in" and that the Garret center section was like a piston ring and once i put some boost through it would seal better.. so the more boost the better the seal.. so i patiently waited..
after some boosting on the dyno and car running for a while turbo still smoking like a ****... so after some research I figured oil has to be pushing past the seal somehow!
so I bought a 1/8 NPT to -3AN aluminum adapter and cut the bevel tip off the AN side just above the threads.. I had a baggie full of nitrous jets leftover from a NOS project, so I put the adapter in a vice and got a drill bit just the right size of the bottom of the nos jets (if you look up a pic of what the jets look like you will see the little nub they have) vasically your making the angled side of the jet the tip of the adapter and thats whats going to seal against the -3AN line. now basically go down in size until the smoking stops..
of course try this at your own risk. im not responsible for damaging your turbo. BB turbos require way less oil than journal turbos so the amounts will differ but done right this method will basically feed the turbo just the right amount and not the excess to burn off in clouds of smoke...

the end! :p

 

WOW, chameleon, that's a lot of work just to find out that a GT4088R (considered to be a large frame) uses the same journal bearing resrtictor for that size (.065") to stop oil blowby

 

so do you think my turbo is bad? i dont see how a seal can be blown. its metal. oil just pushes past it. i only put about 2 miles on it

 

No. just too much oil pressure. Get a guage and check to see what the pressure is at Cold start. also, check your return line to make sure there is a smooth downward transition. no 90 degree bends of any kind. otherwise, you'll cause a backup which acts like something is wrong.

 

oil pressure is around 60-70psi on cold start

 

I never said what size mine is and definitely not the same journal bearing restrictor, I didnt do all this because it said so somewhere, just like my piston rings are gapped a different size than yours are.

 

so your turbo quit smoking? did it perform well after that? i took apart my turbo i thought was blown, other than some burnt oil in the exhaust it looked just fine. i cleaned it up, put it back together and it was just fine. no shaft play. it spins good.

 

The GT4088R utilizes a .065" or .060" restrictor for -3AN lines that use oil pressures from 75psi-100psi. You're right, it may not be yours exactly, but that is more of a standard range.