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SII RB25DET turbo?

DETurbine

By DETurbine,
in Engines & Forced Induction

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DETurbine Enthusiast

DETurbine

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I have a RB25DET Series 2 in my USDM 240sx S13. The motor has 30k on it and is healthy. I right now have the stock SMIC, but within about 2-3 weeks I am going to be putting on a Pro-Charger FMIC that will be able to support up to 800HP. My question is I have heard that the stock turbo can handle more boost if it has low miles on it and is healthy. I know it has a ceramic wheel and is held on the shaft by a strong glue and over time with high amounts of boost will break apart and shoot the turbine wheel out the exhaust. I am running 10psi right now, but plan on taking it up to 15psi once I get the FMIC on there. Do you guys think I will be safe with the turbo only having 30,000 miles on it?

How long do you think the turbo will last?

I will have a T3/T04e .63ar on it by next summer, so I am not going to be running the stock turbo for that much longer.

Let me know,

Thanks

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siksII Grand Master

siksII

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the stock turbo runs out of efficiency at 10-12 psi so there is no point.. and there are plenty of people with experience that shows that the stock turbo wont last long if your boost it higher than 12 psi..

it will last even less with the stock cooler, once u add the fmic it will be safer to run that boost and it will make more power. (lower pressure drop)

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DETurbine Enthusiast

DETurbine

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the stock turbo runs out of efficiency at 10-12 psi  so there is no point.. and there are plenty of people with experience that shows that the stock turbo wont last long if your boost it higher than 12 psi..

it will last even less with the stock cooler, once u add the fmic it will be safer to run that boost and it will make more power. (lower pressure drop)

From what I have been told it is pretty much the same turbo specs as the S15 T28, added on the T3 flang, ceramic wheel, and different make.

I know the T28 are found to go up around 17psi and still be efficeint.

What is limiting the RB25 turbo to only 12psi?

So by adding on the FMIC you think it will be a dramatic power change from the stock SMIC?

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USRB25S13 Enthusiast

USRB25S13

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Before you crank up the boost beyond 12 PSI You should look into some kinda fuel controller to get maximun perfromance from the increase boost. I ran my SII Motor at 12 PSI stock IC and no Managment without any problems. I am sure it would have made more power with some fuel taken out up top. I now have a 56 Trim T3/T4 on the car and I am still running stock SMIC and stock ECU. At 9 psi the car will hit boost cut every so often. I have an FMIC + PFC on it's way so I can start to make some real power.

Anywho.....Run 10-12 PSI and you will be fine. Anymore boost then that and you are starting to ask for trouble.

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Lithium Grand Master

Lithium

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From what I have been told it is pretty much the same turbo specs as the S15 T28, added on the T3 flang, ceramic wheel, and different make.

I know the T28 are found to go up around 17psi and still be efficeint.

What is limiting the RB25 turbo to only 12psi?

So by adding on the FMIC you think it will be a dramatic power change from the stock SMIC?

The RB25DET turbos have a ceramic-type exhaust wheel, and as far as I understand at high speeds/temps they can break off and head off for more carnage - so its not just efficiency thats not going to be ideal.

But on efficiency, as far as I understand a turbo's efficiency is measured on turbine rpm vs. air type scale - so maybe an RB25DET demands in the same area of turbine rpm from the turbine for 12psi as an SR20DET does to be pressurised to 17psi, being a bigger motor and all.

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