Turbo Oil Scavenging/draining?

JMA-RUF · 08-03-2006, 02:23 AM

Hi all,

I'm collecting bits for my 3.2 turbo conversion and am after advice for the oil draining from the turbocharger.

I'm using some aftermarket 930 headers, so I want to know what the best solution is for draining the oil back into the engine.

Does anyone have any pictures of gravity drain solutions for me to look at?

I found these in the Parts Forum and whilst it looks like a good and easy solution (draining to the lower left CAM cover), I'm concerned that oil may back up into the turbo under hard acceleration, causing premature wear

I'm hoping "Porsche Doc" will tune in here and put my mind at ease.

My other option is to drain to the chain cover housing, which I believe some of you guys have done with your Proto conversions.

My problem in doing that is that I want to use any normal 930 muffler, so it all mates up OK. If I fit spacers between the collector and turbo, I'm worried any normal 930 muffler won't mate up to the turbo sitting a bit higher.

Also, what's the best way to do the fittings? Is it better to weld a 5/8" barbed fitting to the cover of choice, or just tap the cover for a screw in type fitting, like the ones used above?

Opinions please?

JMA-RUF · 08-03-2006, 02:36 AM

Also, how thick is the aluminium chain cover housing?

I'm thinking of having it tapped so I can screw in this type of fitting (1/2" NPT male -> 5/8" Barbed):

JMA-RUF · 08-03-2006, 04:47 PM

Anybody?

mmastro · 08-03-2006, 07:58 PM

I'm probably not helping much at all, but I thought I'd post pics of a 3.0L turbo oil scavenge unit (with headers). (Pics from tank to scavenge pump.) for comparison.

I'm no expert on the 3.2L Turbo conversion, but I'd think that the oil pump pressure into the turbo (at hard acceleration) would be enough to not let the scavenged oil backtrack into the turbo. I'd be concerned with the idle oil pressure not being enough to keep the oil at a one way flow.

JMA-RUF · 08-07-2006, 06:02 PM

Anyone else know?

tsuter · 08-07-2006, 06:07 PM

The left chain cover lower corner works... 5/8" inch hose about 4 inches.

tsuter · 08-07-2006, 06:11 PM

Here is a drawing of where/how you tap the hole in the chain cover.

JMA-RUF · 08-07-2006, 06:42 PM

Thanks Tsuter! Great info!

Will that location be suitable even for a turbo positioned using any 930 style header? i.e: will it line up OK with the oil exit port on the turbo?

patkeefe · 08-07-2006, 06:46 PM

As tsuter says. not a lot of pitch, but it will drain. Mine is getting an AN-8 line tomorrow.

tsuter · 08-07-2006, 06:49 PM

The oil drain/exit on the turbo should be at 06:00 O'clock and the drain hose to the chain cover should be horizontal or sloped slightly. The turbo must mount high enough to accomodate this.

JMA-RUF · 08-07-2006, 08:04 PM

I've thought about electric pumps, but I want a more reliable solution. Electric motors tend to (& will) fail over time. I want something a bit more permanent.

Pat, is that J-Pipe positioning the turbo in the typical 930 location?

JMA-RUF · 08-07-2006, 09:04 PM

I wonder if that problem was the result of them not mounting the turbo high enough? I'm going to put a 1" thick flange between the collector flange and the turbine inlet. That should put it high enough to drain back better, I hope

It just means I can't use a normal 930 muffler. I'll have to get one custom fabricated