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I'm in the process of running in my fresh rb26 motor and seem to have a pressure problem. I have a new electric AutoMeter oil pressure gauge installed, and after start up, it idles at aprox 75lbs. of pressure....

When I drive around, it peggs the needle at 100lbs. (max reading). I'm sure the pressure is going higher than 100lbs.

Once warmed up to operating temp., the idle pressure settles at aprox 25lbs., but under boost, it stays at, or over 100lbs. I'm afraid this is to much, and I see oil coming out of my new Garrett 2540's comp housings....

Is this normal for the Jun pump to be that high of pressure? I have the Tomei oil restrictor installed in the block.

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Thanks.... I guess its possible to adjust the pressure via the spring, correct?

pressure is caused by a restriction in flow...

u have put a restriction of flow in the head plus the jun oil pump flows more than standard.

i have a jun oil pump which runs around 8-8.5bar of pressure on cold start

Edited by RB26zcar
pressure is caused by a restriction in flow...

u have put a restriction of flow in the head plus the jun oil pump flows more than standard.

i have a jun oil pump which runs around 8-8.5bar of pressure on cold start

What he is saying is...the Tomie oil restrictor is adding to the pressure you are experiencing.

easy except its an engine out and sump off job to get to it :)

my jun pump has over 100psi when revving when cold and around 80psi at idle. when warm its about 28psi at idle and 75-80psi at full revs, i have the restrictor in the head also.

Edited by overpowered

i tto run the jun pump, an i have 100psi on cold start, with a tomei oil restrictor, when warm the idle presure drops to 28 psi and on full song its 80 psi. i have a restrictor fitted in my turbo feed line, but not sure if the T04Z comse with a restrictor fitted in the cartridge. have ask the experts on that. i run the stnd tension spring

http://www.turbobygarrett.com/turbobygarre...r/faqs.html#t16

Does my turbo require an oil restrictor?

Ball-bearing turbochargers can benefit from the addition of an oil restrictor, as most engines deliver more pressure than a ball bearing turbo requires. The benefit is seen in improved boost response due to less windage of oil in the bearing. In addition, lower oil flow further reduces the risk of oil leakage compared to journal-bearing turbochargers. Oil pressure entering a ball-bearing turbocharger needs to be between 40 psi and 45 psi at the maximum engine operating speed. For many common passenger vehicle engines, this generally translates into a restrictor with a minimum of 0.040" diameter orifice upstream of the oil inlet on the turbocharger center section. Again, it is imperative that the restrictor be sized according to the oil pressure characteristics of the engine to which the turbo is attached. Always verify that the appropriate oil pressure is reaching the turbo.

The use of an oil restrictor can (but not always) help ensure that you have the proper oil flow/pressure entering the turbocharger, as well as extract the maximum performance.

All new Garrett Turbo charges have a restrictor build in on the oil intake.

Adding one in the line does not make any difference(Just piece of mind) and does no harm to the turbo charger.

The problem that RB26zcar is having is high Oil pressure caused by incorrect research into re-build .

Some one has got it wrong when fitting these Tomie oil restrictors.

Blow by will be large when racing this car...you might need to add a larger sump extension and a larger than life oil coolerto increase the volume of oil..thus decrease pressure.

This will also help with continuos supply of oil to the head.

Top head pressure can also be decreased I believe by opening the oil restrictors closed on RB26 Heads.

I believe this topic has been discussed before(Oil flow)...do a search.

Do not run the car in its state......you have been advised incorrectly on the build.

Interesting thread, this is the first time I have heard of potential issues with the JUN pump run in conjunction with the Tomei restrictor.

I know a few people who are using JUN pumps and the main thing to remember is a big sump is a must IMHO

All new Garrett Turbo charges have a restrictor build in on the oil intake.

Adding one in the line does not make any difference(Just piece of mind) and does no harm to the turbo charger.

If the std turbo's restrictor were to see 100psi more oil would be flowing in to the turbocharger than if it were seeing less oil pressure caused by the addition of another restrictor further up the line.

Is my understanding of oil flow/restrictor wrong? It could be as I'm simply working of what sounds logical.

Humm... I would have thought my 8 ltr custom baffled pan would have been plenty of oil for a daily driver w/o track duty....

I find it kinda hard to "get it wrong" when it comes to installing a Tomei oil restrictor.

BTW, I'm asking for advice about the Jun pumps gauge preasure, on average, not how well you think I advised myself on my build... Thank You!

All new Garrett Turbo charges have a restrictor build in on the oil intake.

Adding one in the line does not make any difference(Just piece of mind) and does no harm to the turbo charger.

The problem that RB26zcar is having is high Oil pressure caused by incorrect research into re-build .

Some one has got it wrong when fitting these Tomie oil restrictors.

Blow by will be large when racing this car...you might need to add a larger sump extension and a larger than life oil coolerto increase the volume of oil..thus decrease pressure.

This will also help with continuos supply of oil to the head.

Top head pressure can also be decreased I believe by opening the oil restrictors closed on RB26 Heads.

I believe this topic has been discussed before(Oil flow)...do a search.

Do not run the car in its state......you have been advised incorrectly on the build.

Edited by RB26zcar
Top head pressure can also be decreased I believe by opening the oil restrictors closed on RB26 Heads.

I believe this topic has been discussed before(Oil flow)...do a search.

The whole aim of the Tomei restrictors is to reduce oil pressure in the head as it retains too much oil, opening it up would defeat the purpose of putting the restrictor in. I suggest you yourself do a search on oil control.

Maybe put a gauge on it that reads a bit higher to actually see how high it goes, Mcstocky is correct though, a softer spring in the releif valve will fix this. An oil cooler will make almost no difference.Do you know what the main and big end bearing clearances are? If they are too small, there will be higher oil pressures, but the bearings will cook, as the oil cant get out of them(hope not)

Edited by Adriano

Did you replace the braided oil lines?(To turbo's)

And if so......did you go one size smaller?

Reason I posted up the previous remark was in concern for your motor.....I know what you were asking.

Hope I have helped.

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