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I would appreciate if someone recognises the situation below and gives me some advice.

It was the cars first few laps at a circuit. I noticed plumes of whitish/blueish smoke after exiting Southern Loop (turn 2) on the first hard lap. I backed off immediately thinking it was a broken turbo. Into Honda the smoke was less but still there. I continued on at gentle throttle towards Siberia (another left hander)to get more diagnostic information. Lots of smoke on exit and again at Lukey Heights. I brought it back to the pits.

On the track the turbo (stock SE) was still boosting ok but with just a tad less power and lots of smoke. In the pits I noticed the alternator belt was chewed about so I replaced it and continued to look around at the engine bay and hoses. There was oil spitting traces from the electronic boost controller, so oil is coming from the inlet plenum via the vacuum hose. I disconnected the breather hoses from the head and they all showed oil. The breather pipes are all plummed back to the turbo inlet and showed oil. Before the event, the oil level was just over the "f" line (about the width of the line and after driving to Phillip Island from Melbourne and five hard laps and 3 slow laps the oil level was three quarters full.

I suspect, that under hard cornering, oil blow by is finding its way into the turbo air inlet, through the turbo, intercooler and piping and being burned in the engine making a lot of smoke. In addition, it's possible that a thrust washer is shot in the turbo. At the end of the day I took a straight back road and hammered it. Plenty of boost, acceleration but no smoke. Power was also better than earlier in the day on the track. (Maybe not a turbo problem).

The car has the standard oil return system from the factory and does not have an external catch can. I'm thinking an open to atmosphere catch can system may fix the problem. I'm not worried about legality. What do you think? Is there another explanation?

Also, what do you think is going on with the alternator belt. The new belt is showing some stress already. Is there a fix for track cars doing high revs? It "chirps"on start up when cold.

The SE's integrated Catch Can system isn't much good. Oil tends to make it's way back up the sump return pipe and into the intake. The quick fix is a check valve ala FM's Kit (https://www.flyinmiata.com/msm-check-valve-kit.html), but really you want a decent catch can.

Are you thinking that both the MSM check valve and a catch can is required or just a catch can system?

For me, it'd be either/or. However if you retain the oil drain with a catch can, you'd probably still want the check valve.

I'm now just running a proper catch can system, this is the one I have, but there are many others you could piece together. See Lokiel's "Gina" build thread for his solution (and a good read in general).
https://www.nitrodann.com/product/nb-se-catch-can/

Here's the best picture I can find of it installed in my engine bay, hiding over on the right behind the piping and the airbox. Note, I removed the strut bar as part of my installation.


The check valve is the quick and easy fix. Catch can should give better results, but it's a little more involved, and you'll likely have to block off the existing oil drain.

Yep had exactly the same problem with my SE, Nitrodann catch can solved the issue.

I vent to atmosphere rather than re-circulate.

I removed the factory system but left the drain hose in place (not connected to anything) and just chucked a bolt in the end secured with a hose clamp. This hose is then ziptied to something (inlet manifold I think) so that it doesn't flap around. I've also left the strut bar in place which contains a lot of the pipiing from the factory catch can set up, but have placed rubber bungs over the holes just to tidy it up.

The 'proper' way is as Lachy has mentioned, remove the drain hose and block off the drain inlet at the sump.

I've never had that issue but I have one of these in the drain line from the catch can.

http://www.ebay.com.au/itm/Non-Return-Valve-2400843621-for-MANN-ProVent-200-Catch-Can-Pro-Vent-/251830025102?hash=item3aa23d3b8e:g:Sk0AAOSwr7ZW3NYQ

SE also has the World's Worst Design of turbo to sump oil return pipe. It has a really thin wall and easily cracks, dropping oil on the exhaust, which gets marshals really interested really quickly.

The drain for the factory catch can to the sump is on the drivers side of the engine. If its happening on high speed hard left hand turns I'd put my money on the inertia forcing oil back up the drain pipe into the catch can, over flowing and then being sucked through the intake system.

Install a 1 way check valve in the drain hose and that will stop it. Ultimately plug the drain and install a better catch can.
I installed the 1 way valve on the standard catch can drain and don't have oil in the intake issues anymore. (well not enough to blow smoke or cause issues)

I also high recommend pulling your intercooler and intake pipes and clean them out.
If you lost a 1/4 of your oil over a few laps, most of it will be sloshing around in the bottom of your intercooler