Twin Turbo Oil Issue
 

Alright guys I was holding off on posting to see if I could track down the problem on my own but with so many different opinions and strike outs I need to ask you guys.

So my issue, I'm getting blue smoke (oil) out of the ass end at high RPM shifting. Basically when I lift and shift, back on the throttle it doesn't do it. I have had the Huron kit now for two race seasons, I love everything about it other than the oil evacuation. So I had to rebuild a turbo this spring (Precision 6266 .82 AR), oil in exhaust housing. I upgraded the return pump last year hoping it fixed the issue which it did not. The car doesn't smoke on start up, not idle, not normal driving. This leads me to believe a few things, drain issues which I can't imagine (-10an return lines and -4an feed), possibly adding a restrictor (a no no on journal bearing turbos), catch can routing or god forbid I'm pushing oil through the rings, I have not done a leak down.

I run the MM wild kit (-10an), I attached the image of my routing, yes not the best but I did it quick to send to Dave at MM, and really didn't get a straight forward answer if this is the best routing/setup for my application. He did suggest up sizing the nipple on pcv valve itself. So this is where I need your help, I cannot continue rebuilding turbos every spring. Well, if that's what it take then whatever, but I would prefer not too:rolleyes:. I'm hoping no one else has my issue but if you have or had similar issues please help a guy out, thanks!

Car info:
HSP twin kit
PT6266
4an feed, 10an return to oil pan not cap
exa-pump
FIC 1000
Fore dual 450, -8an feed stock return
TSP springs, retainers, push rods, trunions
TSP stage 2 turbo cam

Attachment 990223

What oil pump are you using?

Where is your return located exactly, could you plumb the return to the fill cap/valve cover easily? I wonder if oil is sloshing into/over the return and blacking up the oil flow

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I have an AGP kit and when I was manual I would push smoke between shifts. it has nothing to do with catch can or PCV.

What happen is you are sitting at an amazingly high number of pressure in the turbine or compressor, when you let off and that goes from lets say +15 to -20 vacuum. that vacuum pulls or pushes oil through the seals in the turbo directly into the hot exhaust which vaporizes it. its just one of those normal things you will get used too.

Had the same issue and it was a turbo doing it. My guess is somehow oil was getting past the seal and into the turbine housing. Essentially anytime going from boost to high vacuum like mentioned above. I have an agp kit as well and that same turbo ended up seizing up and AGP sent me a replacement and it never smoked again.

Turbowerx Exa-Pump, my I tapped my pan on the passenger side. I am running the MM wild can and that uses the oil cap location, that's why I tapped the pan instead.
Attachment 990609



I know its not the end of the world, just more concerned about having to replace seals more often then I would like, thanks for chiming in!



Yeah, and I do know Precision is known for having to rebuild turbos more than other brands, can't win I suppose! Thanks for chiming in!

Words of wisdom!

Probably need to adjust your airflow final minimum table to not close the throttle so tight at higher airflow points. Anything that changes how much air your engine ingests requires this table to be readjusted. Change cam, displacement or even just porting heads.
Not doing this will create vacuum in the exhaust manifold and suck the oil through the turbo and into the exhaust stream for a second.

I will check with my tuner, thank you!

Exactly !

It's a daft notion that could occur.

how much smoke are you actually talking about, and are you sure it's oil ?

Like clouds of it ?

And you're breather drawing appears to have one valve cover connected directly to a turbo inlet......with no oil/air separation or filtration. That would obviously draw air into the turbo inlet.

Unless the drawing is inaccurate.

I had that issue with my journal comps, I added restrictor at the Y where it fed the turbos. Kept going down in size until no smoke.
I’ve since went to the oil less version so all good.
Good luck tho

I'm getting a puff of blue smoke so oil, I wouldn't say its a lot but noticeable to me in the rear view mirror. Yes the driver side valve cover is connected to the intake pipe on the driver side turbo. This catch can routing and can setup is via Mightymouse Dave himself.

I have my MM can routed the same way. Trust me its the turbos.

My was doing that, I redid the lines for the PVC. The mighty mouse can has the one way fillter? I plugged the valley cover.

Correct, mine has the one way filter in the can and my valley port is plugged.