Oil Control In Rb's For Circuit Drag Or Drift

[Simon-S14]

Interesting. I'm about to pull the head off of my NEO engine. Jonno, What would you suggest to do with the restrictors if i'm retaining the factory N1 oil pump the NEO comes with.

I tried to follow sydney kids table as best as i could and also worked out the cross sectional area of different size restrictors. But still pulling my hair out as to which one to choose.

Now going by Simon-S14's NEO which is a full on drift car which sits on the limiter like no tomorrow, he says he has no issue with oil pumping into the head. However he is at high revs for shorter periods of time than a circuit car.

I was thinking of blocking the centre oil feed as per SK's table and maybe going down to a 1 - 1.3mm oil restrictor in the rear.

Any thoughts?

haha your kidding right? last winton matsuri event i was out there 30 mins at a time thrashing the crap out of it.. come back in and catch can is dry. neo's dont have oil control issues.. its only an issue when parts get changed from non standard.

[kitto]

haha your kidding right? last winton matsuri event i was out there 30 mins at a time thrashing the crap out of it.. come back in and catch can is dry. neo's dont have oil control issues.. its only an issue when parts get changed from non standard.

You just have mad luck

[Simon-S14]

nah.. neos are just awesome... i'll prove it by borrowing your engine if you like

[djr81]

I couldn't do 2 laps without filling my catch can. I had a reinmax pump and revving to 9200rpm on a 3ltr. Changed the restrictor to 1.1mm from 1.5 and installed a head drain. I then had not a single drop of oil out the catch can after 20 laps. Cams had plenty of lubrication. The rear head drain hose burnt closed and made no difference to how much oil was in the head. It just comes down to matching your oil pump flow to your restrictor size.

I also had mines triple flow baffles and a 1.1 litre increased baffled sump.

Matt

Matt,

Which Reimax pump was that?

My rb25 has a Tomei pump, 1.1m restrictor external drain, mines baffles, baffled sump and it is an oil puking mess. Cant do three laps without the AFMs getting covered in oil. tis fine on the dyno, however.

I guess I am asking what peoples experiences with aftermarket pumps is like. Because at this point I am seriously contemplating reverting to an N1.

[KiwiRS4T]

Matt,

Which Reimax pump was that?

My rb25 has a Tomei pump, 1.1m restrictor external drain, mines baffles, baffled sump and it is an oil puking mess. Cant do three laps without the AFMs getting covered in oil. tis fine on the dyno, however.

I guess I am asking what peoples experiences with aftermarket pumps is like. Because at this point I am seriously contemplating reverting to an N1.

As per Matt's post above it seems that the so called head drain doesn't (drain). I have just installed 2 x 1.0mm restrictors and drilled two 20mm holes in the sump and fitted 2 breathers (in theory one was going to be an oil return from the catch can if necessary but so far it seems to be working well with the 2 breathers.

If you have an oil drain installed in the back of the head consider as an experiment disconnecting it from the sump and instead fitting a breather hose to the sump running either to atmosphere or to a seperate catch can.

Also the design of the RB26 cam covers is quite different and if you have room for them on your engine they could also help (together with the Mines baffles).

[nisskid]

haha your kidding right? last winton matsuri event i was out there 30 mins at a time thrashing the crap out of it.. come back in and catch can is dry. neo's dont have oil control issues.. its only an issue when parts get changed from non standard.

neither does my RB20 dead set every time i pull the catch can off there's only dust and water in there (sits in the wheel well)

[gotRICE?]

neither does my RB20 dead set every time i pull the catch can off there's only dust and water in there (sits in the wheel well)

Niether does my RB25! Its wierd, maybe its just luck.

Been to tons of trackdays in mine, and coming up to my 4th with the GT30. No oil issues whatsoever.

Overheating yes... oil.. no lol. Stock Radiator cant handle the jandle.

[abr33]

I have run a rear head drain, front sump to cam cover 1 inch breather, catch can to sump return, my own design baffling in the 25 covers ill post pics up eventually if it actually works...

[BoostdR]

The idea of a sump to atmo breather has merit. Reducing blow by pressure in the sump will encourage the head to drain. Position in the dump will be crucial however.

Matt

[kitto]

Position in the dump will be crucial however.

Matt

Seems that as high possible on the inlet side gives the best results. However, what size breather from the sump to the top of the catch can is going to be adequate? I was thinking a single -12 line.

[BoostdR]

I meant in the sump not dump.

-12 should be fine.

[djr81]

Matt,

Which Reimax pump was that?

My rb25 has a Tomei pump, 1.1m restrictor external drain, mines baffles, baffled sump and it is an oil puking mess. Cant do three laps without the AFMs getting covered in oil. tis fine on the dyno, however.

I guess I am asking what peoples experiences with aftermarket pumps is like. Because at this point I am seriously contemplating reverting to an N1.

Sorry I coughed this up. The above post should read RB26.

My question remains - has anyone here put an aftermarket (ie not Nissan/Nismo) pump on their RB26 and successfully run it on a circuit? If so what mods did they run with?

Here is a pretty picture of some Mobil 1.

[KiwiRS4T]

Seems that as high possible on the inlet side gives the best results. However, what size breather from the sump to the top of the catch can is going to be adequate? I was thinking a single -12 line.

I have two holes drilled and tapped as high as possible (and forward of the dipstick) in the sump. Currently both act as breathers with 18mm ID hoses but the intention is that one will go to the top of the catch can and the other come from the bottom as an oil return if necessary. I also replaced the two 1.5mm restrictors with two 1mm restrictors. So far there has been no oil coming out the top - I have hoses from the cam covers going to a seperate catch can.

After I first did it there was some oil coming out of the breathers on the dyno (which caused them to stop tuning at 15psi) but that could be because I put about 7.5 - 8L of oil in the sump (although it has a 10mm adapter plate that was still a bit too much!).

I have now reduced the fill level to the full mark on the RB30 dip stick (so a still a bit more than stock amount of oil). I will now carry out the original plan connecting one hose to the top of the catch can and the other to the bottom as a drain. I have a track day coming up so will see if there are any problems. If not it will be back to the dyno and tune for 21 psi.

If all goes well I will next block off the drain to the sump and see if there is still oil coming out of the breather when there is a sensible oil level. If not I will conclude that one breather is enough (although since you need to pull the engine to remove the sump you may as well drill 2 holes - you can always plug one off if you don't need it versus pulling the engine again if you do!).

[Gerg_R31]

Side drain, no idea what fittings would suit the turbo guys but here is what i did (the rear drain will be moving to the intake side of the sump at a later date)

side fitting speed flow part number 816-08-08

And i used a straight dash 8 fitting on the head, and a 45° fitting for the sump end

[Piggaz]

Where on the 26 head would you drill that feed exactly?

[GTR_JOEY]

whats the thought process for wanting to move the drain line to the intake side....

would just like to add that a doubt very much that the lines from the head to the sump are actually oil drain unless u have severe problems with ur head filling with oil. This is usually rectified by oil restrictors.

I have lines running from the back of my head to the sump and i beleive its used more as a crank case pressure releif through those lines, into the head and out the breathers that i now have plumbed into a catch can that vents to atmosphere.

By relieving the pressure in your crank case this will allow oil to drain quicker down through the galleries.

also as the engine spins clockwise i would have thought the vacuum (if any) would be from the exhasut side

just my take on it, happy to hear any opinions or constructive critisism

Edited March 14, 2012 by GTR_JOEY

[JonnoHR31]

nope vacuum is on the intake side as the crank sweeps up and away from the oil in the sump, forcing that area to draw in air to replace the what the crank has displaced, creating a vacuum on that side. it wouldnt be much but it might make a slight difference if your rings arent perfect

[Gerg_R31]

Piggaz - the 25/26 heads have the half inch npt fitting between #3 & #4 from factory, (10mm hex key needed to remove it) the part number i mentioned screws straight in with a bit of thread sealent

I actually agree with gtr_joey,

If you weld AN fittings onto the sump in line with the cranks counter weights, as the crank moves downwards, the counter weights create a downward suction effect on the exhaust side,

On the intake it will create an upward push effect, which is why i want to move the rear drain to the intake side to act as a sump gas vent

Atm i don't have oil control issues, more planning for future as a "just in case it might happen" oil drains are drilled out in head and block, but didn't fit restrictors (no one had any available at the time)

number 6 piston does have piston knock on cold starts which does have a little blow by, but none after it warms up

(i re used my 3 month old forged pistons after valve float from shitty valve springs. Number 6 piston skirt had collapsed 2 tenths of a thou, and i didn't want to wait 8 weeks for a new set as it is my daily driver)

but yeah i'm aware that the drains are a "band aid effect" but thought someone may benefit from it if they dont want to pull a motor apart just to fit restrictors

[KiwiRS4T]

I don't have drains I have breathers on the intake side and there is no vacuum... the problem is excessive pressure which it is thought impedes the return of oil from the head to the sump. My breathers don't go to the head but to a catch can and the airflow out of the hose is significant. Any way the combination of reducing my restrictors down to 1.0mm each and fitting the breathers to the sump has cured my engine of spewing oil everywhere. I also have hoses from the cam covers going to another catch can and that is not now collecting any oil.

[r33_racer]

Ill post it again in this thread cause I love putting my ms paint diagram to use! WOOOT!

I dont have the side or rear head drains drawn in as they arent really needed if everything is setup properly and engine is built well.

Lol even though on my road car I have put in the side drain also as it is the lowest point in the head.