Anyone know 20g recommended oil pressure range?

[AL92]

I have tried search to find out what is the recommended minimum and max oil pressure recommended for mits 20g turbos.I have a 99 trans am with two 20gs in the system from APS and few other guys seem to be having problems with oil past the seals .Think they are running high pressure and might need restrictors. I thought only the BB turbos needed restrictors.

So anyone know the min and max spec for 20gs?

[spendone]

mitsu turbos have restrictors built into them.

[Burnett03]

He's right. You can feed a mits turbo upwards of 100psi and the seals wont blow as long as the return is kink free and not blocked.

[jusmx141]

Originally Posted by spendone

mitsu turbos have restrictors built into them.

I agree.

There are visible restrictions built into the oil supply hole of a M.H.I. center housing. This will reduce volume, but not pressure. You're still required to find an oil source with the proper operating pressure.

Compare the oil supply holes of a M.H.I. turbo (first) to a Garrett (second) to see the restriction:

Originally Posted by Burnett03

He's right. You can feed a mits turbo upwards of 100psi and the seals wont blow as long as the return is kink free and not blocked.

I don't agree.

I recently had a customer run one of my freshly rebuilt 16G's to the filter housing on balance shaft-less 7-bolt, and it DESTROYED the journal bearings and scored the turbine shaft in only a couple hundred miles. The same has happened to Garrett turbos fed from the filter housing on balance shaft-less motors on numerous occasions. Apparently too much oil pressure can do just as much damage as too little.

Honestly, I believe Mitsubishi knew what they were doing when they ran the oil feed to the head on 1G's with 14B's. There are 14B's out there with 150K+ and they're still boosting, while the majority of T25's on 2G's (supplied to the filter housing) died in the 80K-120K region.


To the O.P.- The Mitsu turbos should restrict volume themselves....I would find an oil pressure source that doesn't exceed 60psi at wide-open throttle.

[Burnett03]

Originally Posted by jusmx141

I agree.

There are visible restrictions built into the oil supply hole of a M.H.I. center housing. This will reduce volume, but not pressure. You're still required to find an oil source with the proper operating pressure.

Compare the oil supply holes of a M.H.I. turbo (first) to a Garrett (second) to see the restriction:






I don't agree.

I recently had a customer run one of my freshly rebuilt 16G's to the filter housing on balance shaft-less 7-bolt, and it DESTROYED the journal bearings and scored the turbine shaft in only a couple hundred miles. The same has happened to Garrett turbos fed from the filter housing on balance shaft-less motors on numerous occasions. Apparently too much oil pressure can do just as much damage as too little.

Honestly, I believe Mitsubishi knew what they were doing when they ran the oil feed to the head on 1G's with 14B's. There are 14B's out there with 150K+ and they're still boosting, while the majority of T25's on 2G's (supplied to the filter housing) died in the 80K-120K region.


To the O.P.- The Mitsu turbos should restrict volume themselves....I would find an oil pressure source that doesn't exceed 60psi at wide-open throttle.

I agree and disagree with you. I fed my mits turbo 110psi oil pressure for over a year and 1/2. Never had any seals problems. No balance shafts ofcourse. Worked great. Now this is where i agree with you: I did the same with my garrett, blew shortly afterwards from over volume/pressure. I should add both of these turbo's were fed from the filter housing.

[Boosted98gsx]

Get the RED FP oil filter, take feed from the head, and no worries.

[Strm Trpr]

Does anyone know the recommended oil pressure for a MHI turbo?
When exceeding the pressure requirement, you can actually slow the turbine shaft down causing more lag than necessary.

That was from Dave at Bullseye Power.