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Just after some feedback on my setup after taking the car to the track for the first time with the new engine.

The engine is rb26, -5's and support mods.

Oil mods are, Nitto oil pump, Enlarged oil return holes in block, rear external oil drain to sump, custom 10 litre sump, tomei oil restrictor in block.

The engine is less than 500kms old and it has good internals

Took the car to a supersprint on sunday and the engine blew about 500mls of oil out the breathers into the catch-can. The rocker covers only have standard baffles.

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get better baffles in the rocker covers. Also how is ur catch can plumbed? If its connected to the turbo intKe try running it to atmosphere instead

Its running to atmosphere and it actualy blew a fair bit of oily vapor out the actual filter attached to the catch can.

get better baffles in the rocker covers.

Thats a silly suggestion. Clearly theres a more serious problem at hand, clearly only a bandaid fix IF it did do anything.

Too much oil in your head and you may eventually spin a bearing from oil starvation, the Nitto pumps pump alot of oil.

As others have said, a smaller restrictor may be needed.

Take car back to engine builder? What is his take on the problem???

Would I be right to just fit a different catch can that has a return oil line going to the sump? I could tap into the oil return line from the head and just fit a Y peice into the sump

Well then what you're doing is making a makeshift oil air separator...just buy the proper one as suggested

I dont think its a silly suggestion. I dont think he can really starve the sump of oil. Its a 10litre sump and i doubt the rocker cover will hold 10litres of oil.

Plus he already has a restrictor. He hasnt specified what size yet so cant comment on that.

It has a 1.2 restrictor fitted. And we also removed the spring in the oil pump to lower the oil pressure. I just thought with all of this done as reccomended here in the rb oil guide section that everything would be sweet. I thought wrong

U have done the mods by the sounds of it. Now u should get better baffles so only vapour can exit the rocker covers. As above u should get an autech style catch can/oil air seperator. There only 150ish from memory from ebay or just jap. This will hold a bit of oil under power if needed then once it gets a chance it can dump the oil back into the head

The Nismo can will not put an end to the sort of issues you have described.

Vapour (and oil) still finds its way into the intercooler. Enough to drip out the bovs.

You need to stop the oil getting to the catch can in the first place.

Are you running a PCV? Because if you are not then that will be half the problem.

The Nismo can will not put an end to the sort of issues you have described.

Vapour (and oil) still finds its way into the intercooler. Enough to drip out the bovs.

You need to stop the oil getting to the catch can in the first place.

Are you running a PCV? Because if you are not then that will be half the problem.

If its not connected to the turbo intake (which he said it isnt) then it cant find its way to the intercooler unless a turbo seal is leaking

i think it will be the baffles for sure!

ive got a Autech Can on my car, and after a full track day on a hot day, it has had a smoky exhaust for a good 1-2hours after. i remember the first time i went to the Creek, it was a 30 odd deg day, my oil temp got up to 130deg at one stage, therefore would have been thining right out, when i got home that night i had my car just idling out the front of my garage and she was puffing a heap of smoke, i thought the turbo seals where gone or somthing, took it for a cruise no boost drive by the time i was back, it was all normal again. At the time my Autech was plumbed back into the intake, its now Atmo.....

Change the baffles man, let us no how you go!

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