Oil Restriction

[nissan200sx.dk]

Hi all.

I have searched but cant seem to find a answer.

I am building a RB30/25, using RB25 oilpump, and 1.5mm restrictors to the RB25 head.

On the exhaust side of the RB30 block there is a oil out. I will be using that to feed my GT4084R turbo.

Do i need a oil restrictor before the GT4094R? Or should i just hook it up and leave it using the built in restrictor in the Gt4094R?

Also, there is only one oilreturn in the block, can i hook up, turbo drain, std head drain, and extra head drain to that using a T peice.. (Not T, but with 3 fittings. You get the picture)

Thank you.

Edited August 29, 2009 by nissan200sx.dk

[nemini90]

not to sure about your turbo you will need to find out what presure it can take

as for the drains try to weld fitting onto the sump as its not a good idear to connect them all together as there will be a flow problem

[SLAPS]

Nissan ran 2 restrictors. One at the block and another at the inlet of the turbo.

GCG I believe supply turbo's with an additional restrictor. I reused the factory restrictor at the block on my old GT30 setup and will again be using a restrictor for the new setup.

Its not wise to T in to the turbo's oil drain.

[Kwyjibo]

I understand that the factory restrictors are only on the R32's though but correct me if I'm wrong. I thought that the RB25 had a non BB turbo so didn't need a restrictor.

[Adriano]

Make sure you clean the oil passage that goes through the block, as they are usually full of carbon.

[nissan200sx.dk]

Adriano. Block will be cleaned very good.

Rest:

Garret specify 40 - 45 psi oil pressure on max engine speed, and say"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" And I should always check that this is correct.

Info from garrett here: http://www.turbobygarrett.com/turbobygarre...r/faqs.html#t16

So i need to mount oil pressure gauge for that when running my engine?

I would prefer not to weld in the sump. So i will drill and tap 2 x 10mm holes in block. Both used as return for oil from the head. Will use the std hole in block for turbo return.

Thank you.

Edited September 2, 2009 by nissan200sx.dk

[T04GTR]

NO OIL RESTRICTOR NEEDED. all gt turbos have the restrictor built into the bearing retainer. (oil intel)

do not fit a restrictor

[T04GTR]

a dash-3 braided hose does the pressure drop for the turbo

[nissan200sx.dk]

Huh? No restrictor at all?? I know there is one in the turbo, but I should fit no extra?

This is from Garrett's wesite.

"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"

I will be using RB25 oil pump, with hydraulic 24 valve head fitted with 2 x 1.5mm oil restrictors to the head from block. And 1.5mm restrictor for the VCT valve that will have it own hose. (Drilled in the head, and coming from side of block)

I have NO idea how much flow the oil pump makes with this setup. I have oil pressure for engine and can fit oil pressure for turbo also if needed to make sure. I dont want to blow my brand new GT4094R. hehe