Nope, I just wanted to make sure the turbo was nice and happy since the bearings look a little hot when I had it apart. Never ever had a smoking issue either, just to prove the point that if you have smoking issues the solution is not to use a restrictor or a smaller feed line.

 

Don't catch your point. An S400 may tolerate a -6 feed, but that doesn't mean that certain turbos may not be happy above a certain oil flow rate. Are all the posts I've read about people putting restrictors solving their issue placebo?

 

The bearing clearances inside the turbo determine the flow rate, not the size of the feed line. BB turbos need restrictors because those seals dont handle the pressure as well (as they dont need to like JB units). Most of the turbos we use are oil cooled, so they need a lot of volume to keep from overheating.

Most of the time a restrictor band-aids a smoking turbo, but you are basically starving the turbo of oil. The solution is to upgrade/fix the drain situation.

 

Well said.
Drain is effected by hose size, angle, length, material, oil drain location.
And crank case venting.

 

Well guys, I experimented a bit with breather filters, etc before the dyno and the truck definitely did not like that (strong oil smell). Not sure why, but the oil smell is lightest when PCV is actually "positive" and not just breathing/ venting. Passenger side to turbo inlet, driver's side through catch can and check valve to intake manifold.

I rerouted my turbo drain and haven't smelled any oil since. Even though PCV of any sort is not ideal technically, I am not getting much blowby, and I'm running a conservative tune. My catch can only has a small amount of oil after 5000 miles, so I'm going to leave PCV hooked up since I think my oil smell was probably the turbo drain...

 

How'd you re-route the drain line?
New location?

 

Same basic routing, just improved. I'll get some pics, it goes straight straight down out of the turbo, then just under the motor mount, to a 90 degree hose end and into a welded fitting above the oil level sensor, the entire time at a decline. Previously I had an "addall" clamp bolted to the cylinder head that pulled the drain hose away from the exhaust manifold a bit, bit I believe it was pinching it a bit and it wasn't necessary.