Turbo Oil Pressure Regulator

[r33_racer]

I found a possible solution for a way of managing excessive oil pressure in the turbo. We just started having some issues with oil bypassing the seals on our old turbo and a brand new core from garrett. Turbo is a gt35r. We put new motor together and put old turbo back on...first thing it did was start blowing burnt oil out the exhaust and oil out from the intake....Rang MTQ they suggested to get it rebuilt.....So thats off getting fixed, so we got a new core so we can get things underway.

Fitted the new turbo, same shit, oil pissing out front intake though not as bas as old core, and smoke still billowing out exhaust. Mind you we have always run the 1.0mm restrictor in the feed ontop of the turbo. Not at the block as some have suggested. The answer (or one of) I believe is this adjustable oil pressure reg, I believe the proper term is a pressure reducer. Used in hydraulic applications, its the smallest unit they had and goes from 50-1000psi. As expected we had to run it at lowest, 50psi. So that in combination with the 1.0mm restrictor solved the smoke and oil blowing out the intake. We tried without restricter at first, but there was still a little smoke out back, nothing out front. At the moment with this gadget inline before the oil filter to turbo it holds 50psi when engine sees peak oil pressure. So far after a quick investigation it seems to be working as hoped for. I guess the dyno run and track time will tell if its anygood overall.

Some pics of the setup.

Pretty much goes oil in, out and the bleed off line which we sent to the factory rb25 front head drain port. Obviously when its all set and correct, it will be mounted properly and the gauge attachment removed so its not so huge and space consuming.

Hopefully this may give some ideas for others who want to try something different to just putting the usual restrictors inline...Maybe if someone found a unit that does a lower oil pressure they could post it up here.

The unit we got was from South Cott....the whole unit with fittings and adaptors and gauge was about 350bux....so not cheap by any means...but the block and valve to adjust pressure was only about 150ish...the gauge plus fittings and whatnot added up the extra...so if you got the basics and sourced a cheaper gauge and fittings you could save yourself abit. We did also look at straight pressure reducing valves...with no bleed off...but we were not sure if it would work correctly with flow and whatnot.

If anyone else has toyed with this idea and come up with something simliar or better possibly cheaper feel free to add. I know some people experience this problem with oil bypassing seals and some dont...some use restrcitors and have no further issues, some dont use them and have no issues. Or like us, some never had the problem, then magically it started, and restrictors dont help and want to fix it properly this maybe some kind of answer.

[Duncan]

very interesting solution. I've been having trouble with the excessive oil pressure from the nitto pump pushing past the seals a bit, a pressure releif is a better idea than a restrictor

[r33_racer]

My thoughts exactly Duncan!

Those nitto oil pumps generate high oil pressure. Good for engine, but not always the turbo. Garrett state on their website, for ball bearing cores, max 40-45psi at full noise.

[R31Nismoid]

So you are still just a bit over then.

That's not too bad though in terms of a fix.

What about a smaller restrictor?

[r33_racer]

Yeh, still over by 5psi...but its the smallest unit we could find unfortunately.

MTQ suggested and I believe CGC said the same, was either putting another restrictor in at the block, or putting a 0.8mm one at the turbo. Now thats getting pretty damn small.

Ideally, someone just needs to make one specifically for turbos and have a range from say 30-100psi so it can be used with BB cores and Bush cores like some of the bigger turbos which i think require more pressure.

[9krpm]

Thanks for sharing r33 racer.

I have a restrictor on my Greddy T67 turbo in the honda s2000 as a temporary fix atm and intended to do something like this when I have spare time. The pressure gauge reads 10+ bar in the honda!

[daisu]

Throwing some ideas out here.

An auxillary oil pump supplying to the turbo only, pressure would be unaffected by engine RPM.

Oil could be supplied from the engine sump. A dedicated oil supply would keep the turbo oil completely separate from the engine oil (would keep metal particles out of the turbo core in the event of a mechanical failure).

Would want an oil pressure switch/gauge to indicate loss of oil pressure if there was a failure.

[watt440]

I have the same problem with oil bleeding past turbo , especialy under boost , used a oil siphon unit to cure the smoking , works great , run 2 minutes on start and stop, looking for turbo pressure solution , used 8mm restrictor , rebuilt the garret turbo , where can I find those parts listed by r33 racer , like to get in the know as to how it came out on both , after Dyno did the fix hold? , what was the final fix? Duncan , did you get the oil solved on your sporty as well.

[Adriano]

sooo many commas

[R32 TT]

My thoughts exactly Duncan!

Those nitto oil pumps generate high oil pressure. Good for engine, but not always the turbo. Garrett state on their website, for ball bearing cores, max 40-45psi at full noise.

Can you not just adjust the pressure relief valve on the Nitto to provide less pressure in the first instance? I thought the idea of the higher 'flow' was just so that it could maintain the min pressure required at high rpm - and if you've added oil coolers etc... Does the engine 'need' super high pressure?

Still I do like the idea of the regulator, I fitted 0.8mm restrictors to my -5's, but you're right they are damn small and could easily get blocked...

[watt440]

Can you not just adjust the pressure relief valve on the Nitto to provide less pressure in the first instance? I thought the idea of the higher 'flow' was just so that it could maintain the min pressure required at high rpm - and if you've added oil coolers etc... Does the engine 'need' super high pressure?

Still I do like the idea of the regulator, I fitted 0.8mm restrictors to my -5's, but you're right they are damn small and could easily get blocked...

Blockage dangers eliminated and much better safety with the regulator. Better running circulation under higher rpm as the heat

is way more substancial going with the boost more often. who sells that regulator and components for the rest of the oil lines.

[watt440]

Blockage dangers eliminated and much better safety with the regulator. Better running circulation under higher rpm as the heat

is way more substancial going with the boost more often. who sells that regulator and components for the rest of the oil lines.

[Adriano]

I wonder if an aftermarket (or factory)fuel pressure reg would be up to the temps? Should be about the correct pressure.

[r33_racer]

After dyno run and finally a half day of practice out at lakeside on the weekend netted no turbo oil issues. Still holds the 50 psi max.

As stated in my first post, South Cott is the hydraulic mob i got the regulator and fittings from.

Adriano, I was considering the same thing but was unsure if it would work successfully. I guess it is worth a shot if someone else is annoyed enough to bother with the idea. Suprising how much you can put up with before you actually do something about a problem.

[r33_racer]

Abit more looking around this morning I found this unit

http://www.cantonracingproducts.com/cgi-bi...&key=22-491

Looks to do the exact job required. Would be easy to plumb inline with some smaller fittings to suit the turbo oil supply. It looks alot neater, smaller and better suited for the job as it is designed to regulate engine oil pressure.

That may help someone

[W0rp3D]

Does this problem exist with a standard oil pump with the 1mm restrictor on the oil feed?

[Swiper the Fox]

run 2mm restrictor at the block and 1mm at the turbo...about 10x cheaper.

[watt440]

run 2mm restrictor at the block and 1mm at the turbo...about 10x cheaper.

Any worries about glogging at the restrictors , with the turbo and exaust fuel burn those 550 injectors seem to feed that

carbon right into the oil passing through the turbo, I think I am getting to much of that , I hope some of its due to the bleed issue I am having now. how much oil pressure emits at 6000 rpm on the skyline. The garrett max is 45psi . I think R33_RACER is still holding true at 5 over hitting 50psi, not sure if he also has another restrictor in line for sure though.

[watt440]

Any worries about glogging at the restrictors , with the turbo and exaust fuel burn those 550 injectors seem to feed that

carbon right into the oil passing through the turbo, I think I am getting to much of that , I hope some of its due to the bleed issue I am having now. how much oil pressure emits at 6000 rpm on the skyline. The garrett max is 45psi . I think R33_RACER is still holding true at 5 over hitting 50psi, not sure if he also has another restrictor in line for sure though.

Well done r33_racer , let you know how she fairs thanks.

[juggernaut1]

Wouldn't an in-line filter (aka XR6 turbo) cure blockage worries with running small or multiple restrictors? The filter itself may knock a few psi off the pressure too?

Actually I'm sure hypergear supply in-line filters. http://www.nissansilvia.com/forums/index.p...howtopic=391141 or http://www.cimotorsports.net/motor-sport-p...oil-filter.html

Edited February 16, 2010 by juggernaut1