R33 Gtst Turbos

[gillies2001]

I have 2 R33 GTST turbos, one has a plastic compressor wheel the other a metal compressor wheel.

Which is the best one to use on a RB20 and also what is the + and - of each wheel

Thanks for any advice.

[hypergear]

Plastic wheel explodes under high pressure (should say high shaft speed), but both of their turbine side explodes under high pressure and heat either way. Steel wheel would be still be a better pick.

[GTScotT]

Same shit different smell.

In theory the plastic one is lighter and would spool easier on the RB20. How much of that difference will be perceivable is anyone's guess.

[R31Nismoid]

There is no noiceable difference in reliabilty or anything performance wise.

Get whichever is cheaper.

[bubba]

I have held pieces of a plastic compressor wheel, I have never held pieces of a lunched steel compressor wheel.

[paulr33]

if you have a choice go the plastic compressor wheel

lighter

[beemae30]

Depends on ur boost? I believe the nylon compressor wheel is better for response. Were as the steel wheel is more capable of higher boost 15-16psi. This is pure rumour from threads ive read. Correct me if im wrong,

[R31Nismoid]

So what forum was that all posted on?

I've never seen such threads here stating such things.

Everyone knows 10-12psi MAX for long turbo life. Run more boost, expect it to die due to the ceramic rear wheel.

Compressor wheel makes no difference, simple as that really. Would have just been cheaper to produce. Wasn't a performance decision.

[Hanaldo]

+1 ^

I ran 14psi on my stock turbo, but that's because I didn't intend on owning it for long. Upgraded the turbo after about 3 months. Never had an issue, but I wouldn't run that much boost and expect it to last for ever.

[beemae30]

Ive seen it on a few threads from overseas. But apparently not true. So just out of curiosity why would u swap a 33 turbo onto a 20 when factory wastegate is set at 10 and they happily run at 11-12 ? Not having a dig just asking.

[Hanaldo]

Because psi means nothing. It's the volume of air that matters. 33 turbos flow more. 10psi through an RB20 turbo is not the same as 10psi through an R33 turbo.

[GTRsean]

Compressor wheel is actually aluminum alloy.

Steel wheel turbo's generally refer to the turbine/exhaust side, late designs are actually use inconel exhaust wheels for high temp resistance.

[gillies2001]

Thanks for the replies

On the RB25, Which was supplied first the alloy or the plastic compressor wheel ?

[paulr33]

from memory s1 gtst is alloy, s2 gtst is plastic/nylon

[twistedr33]

Paul is right, i own a S1 33 and its alloy, Also i agree with the above comment about it being cost effecient to make the S2 nylon. Also i agree with Hanaldo, 10psi through two different turbos is not the same, one will flow better then the other to some extent, more psi does not mean more power.

[KiwiRS4T]

So don't forget to swap your old w/g actuator over to your new 25 turbo.