Turbo Oil Restrictor

[sav man]

I just got a pair of HKS GT2530's rebuilt with Garrett parts. I know that HKS put the oil restrictors in from the factory, but i've read that Garrett don't.

I ordered a HKS GTRS gasket kit from nengun, and that came with a oil restrictor. Sould I use it?

Thanks

[R31Nismoid]

I just got a pair of HKS GT2530's rebuilt with Garrett parts. I know that HKS put the oil restrictors in from the factory, but i've read that Garrett don't.

Garrett do, any Ball Bearing turbo correctly built/assembled will have an internal restrictor on the cartridge itself.

You cant see that till you pull it apart though. The pics you have an external ones.

I know the Garrett GT30XX series was a .8mm (if memory serves me correct)

And that was 2 years ago when i had it, so Garrett were doing it back then for sure.

Being Garrett make the HKS turbos aswell, i dont believe you have an issue.

[sav man]

Well MTQ rebuild them, so i'd assume they put them in.

[R31Nismoid]

They dont actually "put" them in.

If you saw the inside of the cartridge you would know what i mean, its on the actual bearing housing itself... so its like that from the production line.

Im sure MTQ will be able to explain in better english

[turbo87]

I have heard with GT3540's some people have been having trouble with leaking turbo seals due to the high oil pressure run by some high performance engines, Garrett supply another oil restrictor smaller than the inbuilt one if people have trouble, not sure if you would need one or where to find them

[sav man]

I only have a stadard pump, so the one built into the catrage should be fine.

Should I use the HKS (restricetd) bolt, or the factory one?

[wrxhoon]

If you don't use the restrictors you are running the risk of blowing your seals.

[sav man]

if i run the external restriktor, and the internal one together. Will it damage the turbo?

[R31Nismoid]

No, as i said... There is a restrictor on the cartidge.

There is only going to be "X" amount going in there whether you run 50 restrictors or one before you get to the cart itself.

If you fit a larger restrictor before the restrictor on the cartridge, then obviously it will slow the oil/volume down to the core, but once it reaches the core its only going to let in what the internal one dictates anyhow so to my limited understanding of fluid dynamics, it makes no difference.

Contact MTQ and see what they say, but i never ran anything more than the internal restrictor for my GT30 and i had an N1 pump etc.

I could name a dozen others who have done the same with thier setups, not one has blown a seal or had adverse effects.

If the twin setup is different, i would like to know why

[discopotato03]

If you look at your second picture you can see the restrictor in the oil inlet hole . Its the hollow mushroom shaped gadget that needs an inverted flare fitting . All these GT25 BB centre sections have them , actually its the stem of the restrictor that does fore and aft location of the bearing pack itself . If its not there the turbine and compressor try to shunt backwards and forwards depending on which side has the greatest thrust load at the time driving its opposite wheel into its housing - not good .

I guess two restrictors can't hurt but I'd rather have the one only in the turbo because it has unrestricted flow to within a couple of cm of the bearings .

Cheers A .

[WilYawn]

I bought my HKS GT2510 used but rebuild off eBay and it came with a restricted bolt. Do I need it or is the restrictor build in the housing?

[discopotato03]

I can't see any problem with it but if your concerned talk to a HKS rep and ask what their kits sell with these days .

[r33_racer]

well up here in qld there have been a few people blowing seals out at the track...gt30s and 35s alike. Alot of people are now starting to run an inline restrictor that sits right before the cartridge one. I think its about 40psi of oil pressure is the max required for the turbo. Does that sound right disco?

Edited November 20, 2006 by r33_racer

[sav man]

I still havn't got round to contacting MTQ. been to busy doing other stuff on the car to worry about putting the turbo's on yet. I'll post MTQ's responce when I get round to ringing them.