Rb26 Oil Control On Circuits

[djr81]

Needing some help - I am trying to find someone who is running an aftermarket (not a Nismo ro Nissan) oil pump on their RB26 and who runs it regularly on a circuit.

Reason being I followed the advice in the forced induction oil control for RB's thread and have an oil puking mess to deal with.

The pump I am running is a Tomei one - but anything in that flow/pressure range ie Nitto, HKS , Jun etc etc is much the same.

So the question is what other mods or combination of mods dealing with flow & oil/air separation in the head are people running?

I have done the tiny 1.1mm restrictor (As an aside does anyone know where to get a really small one from 1mm or less?), the external drain the mines baffles, the Autech can, the Nismo can etc etc etc.

Car is fine on the dyno but hopeless on the circuit.

Anyway if anyone could help I would be very appreciative.

[sav man]

what weight oil are running, and what pump pressure?

[djr81]

5W50 Mobil 1

Oil pressure is basically as per the chart. Column to be read is third from the left. If anyone could help with the Japanese on the table that would be really helpfull too.

For what it is worth the aftermarket pumps appear to run a couple of bar higher pressure everywhere than an N1.

Edited February 1, 2012 by djr81

[sav man]

Our R33 N1 Targa car runs a Greddy pump, but with the pressure dropped to 75psi. If you havn't changed the presure (which is meant to be easy with those Tomei pumps, as they have external adjusters), it will be ~150psi.

[djr81]

Cant be 10 bar, surely. 150psi = over 10kg/cm2. On the gauge it reads in line with the table that Tomei provide. Which is in the range of 4 to 6 bar or call it 50 to 85 lbs.

But yes a pressure drop (below what may just be possible for the three shims) could be the answer.

Who/how did you get yours done?

[sav man]

My tuner did it, who conincidently runs a Tomie pump on his 560 rwkw circuit car. I'm sure for his, he modified the needle and shim stack to get it down to 75psi. I'm not sure what they did to the Greddy one.

[djr81]

Can you help me out with details of the head mods, catch cans etc for the 33?

[DCIEVE]

Out of interest have you done a leak down test on the engine? When I spoke to your engine builder about taking on my build he suggested ~20% leakdown was a good result for a new engine.

[sav man]

Can you help me out with details of the head mods, catch cans etc for the 33?

The engine is a std N1 long motor with only the oil pump changed. I'll draw the catch can setup tonight for you

Edited February 1, 2012 by sav man

[DJRIFT]

Out of interest have you done a leak down test on the engine? When I spoke to your engine builder about taking on my build he suggested ~20% leakdown was a good result for a new engine.

that seems high.

[The Bogan]

My TOMEI pump was running around 130 psi on the lowest setting, installed a regulator which got it down to 90 at 6000rpm, kept spewing oil though, its got head drains and the catch can returns to the sump, internal drains have been drilled and chamfered, at this stage the VCT has a 0.6mm restrictor and the head is now feed with a 0.8mm restrictor which has been taped into the oil galleries, this makes changing the restricters a 5 minute job.

1 x 1.5 for the head, oil

1 x 1.0, oil

Changed head restrictor to 0.8mm

Still haven't tried out the smaller restrictor as yet.

Wakefield in March will be the next time the car is out.

This oil surge issue has done our heads in.

Goodluck.

[The Bogan]

Pics of my head feed, the restrictors in the head were blocked and the feed is taped into the oil galleries of the head.

Pics of the regulator for the oil pump which got the pressure down.

[GTRNUR]

Im using a Tomei pump too and though I'd kicked the full catch can issue until I drove the car around Winton. Sure the engine does have some blow by, but show me an engine running above 1.8 bar that doesn't. In a straight line or on the dyno has proven itself to be fine. The return drive from Victoria of over 3000km put only moisture in the catch can. No oil.

I believe that at Winton the long 3rd gear left hand corner(3) was my main problem. Its a 4500-5000 RPM corner so your oil pressure is up and head filling is at its worst. Then when you factor in that there are no oil drains on the right side of the engine the oil all collects in the right cam cover. This is where the 2JZ really has it over the RB's with drains along both sides of the block (logical)!

The only hope to control oil flowing out the cam covers really is to drain it back to the sump. The return setups that seem to work all return from a forward mounted catch can, and return back to the sump on the right side of the engine. The disadvantage of this is that the forward placement allows moisture to condense easily and then return as sludge to your sump. Which is ok if you change the oil before and after each track day immediatly, but is not ok for a street car.

I believe the best setup is to do what Nismo do. Put the catch can next to the ABS unit where it is hot above the turbo's, and where it can return via the turbo oil drains. The heat in that area will help seperate oil from water vapor in the blow by gas, and reduce oil contamination as a result.

You could then optionally connect that can back to the intake, or to keep oil vapor out of your induction system you could vent it through a second forward mounted catch can.

Thats my thoughts anyway.

[djr81]

Out of interest have you done a leak down test on the engine? When I spoke to your engine builder about taking on my build he suggested ~20% leakdown was a good result for a new engine.

Not that I know of. But I reckon blowby would have to be massive to get the sort of mess you see in the photo & in anycase I have no reason to think there is any worth the name. The photo was after three warm up laps & three fliers at Wroo.

The motor was built with extra care verging on paranoia and run in on the dyno, then run in some more on the road.

As I mentioned earlier it is fine on the dyno. Nothng coming out of the breathers. Take it to the track and there is oil in abundance.

My thought is the extra time at higher rpm is allowing oil to accumulate in the head - add some cornering gees and you get a mess. Am contemplating running an N1 pump as a fix. But only if I cant nut out a better solution for the Tomei pump.

I was sort of hoping someone had done track work with a name brand Japanese pump. I cant think of anyone over this way fitting that description.

[The Bogan]

Mine is fine at the drags, fine NOW at Easter Creek (lots of left handers) but with a 1.0 mm restrictor it still over flowed the can at Wakefield ( lots of right handers), Ive been told that a oil to air seperator prior to a catch can fixes the problem, if mine is still spewing oil I will fit a oil to air seperator as I cannot go below 0.8 mm as under 0.8mm blockages scare me, either that or go to a N1 pump and start playing with restrictor sizes again.

After 3 warm up laps it only took 3 or four hot laps till oil overflow, even with a bloody return line from the can to the sump.

Mine is a 25/30 which I dont rev over 7300 (I Shift) so a N1 would have been fine but I went for the best I could get (apart from a dry sump) and it has bitten me on the arse, my motor has Fuc all blow by too.

Oil is 10W 40.

I never had a issue when it was a stock RB25.

[djr81]

Pics of my head feed, the restrictors in the head were blocked and the feed is taped into the oil galleries of the head.

Pics of the regulator for the oil pump which got the pressure down.

Where does the head feed get its feed from?

[The Bogan]

Its tee,d into the where the oil pressure (edit)sensor goes, from the oil pressure gauge a line takes it to a tee, one feed from that tee goes to the head feed and the other to the VCT.

[Deano 1]

ive got a bran new tomei pu@p sittin in a box in my room.... this thread is making me worrie

[The Bogan]

WORRY, Its broken my brain.......not hard really, but you know, meh

[DCIEVE]

that seems high.

Agreed.

I was sort of hoping someone had done track work with a name brand Japanese pump. I cant think of anyone over this way fitting that description.

I don't think many of them do the speed series events but plenty of the AL guys are in high hp gtr's that get punted regularly at no limits events etc. The thing they all seem to have in common is xspeed so they must have there head around the problem.