Back in the game, and need a little advice...

JAMCAR223

Well-Known Member
Joined
Apr 28, 2014
Guys, I have been out of the game for a couple years, and have not driven my car in over 2 years. Other projects, stupid Covid, and life in general has gotten in the way. I want to buy a new turbo, new oil feed, and new oil drain for my car. Specs of the car are in my signature. If you can't see it because of a mobile device here it is.

1987 GN - 109 + .020 block / ARP rod bolts, head bolts & main studs / Weisco forged pistons / Comp 210-215 roller cam / Ported stocks / PT51 / RJC Power Plate / Lorenz boost controller / 3" THDP / Duttneck SLIC / 80lb. injectors / Walbro 340 & hotwire / Billet AFPR / TT 5.7 chip / AXIS / LS1 MAF / K&N 12" cone / Pypes 2.5" dual exhaust / D5 / 3.42's / Spohn front UCA's / Hotchkis rear U & LCA's / QA1 coil overs (x 4) / 18's & 20's / S10 Blazer front brakes & cross drilled rotors / Aluminum rear drums & S10 rear cylinders / Jeep steering shaft / Alum. radiator / Intrepid dual fans

My old school PT51 is smokin like a steam train, and has gotten worse over the last couple years. My oil drain is completely clear and unobstructed, so I am assuming the turbo is leaking from the exhaust side. I'd like a newer style turbo, and I'm considering the Precision PT 5831 MFS w/ Buick .63 AR housing.

I would also like to purchase this new oil feed & return kit from GN1.

Would you guys agree with my decision? When comparing the specs from old PT 51 to new PT 5831 MFS they share the same HP rating of 585. They share the same inducer wheel size of 2.290" and they share the same exducer wheel size of 2.950". They also share the same inlet size of 3", and the same outlet size of 2". The main difference seems to be the wheel style PT 51 = T350 where as the PT 5831 = T31. Can I assume this is the difference between old school and new school??

I do not want to change my setup too much as my car has always been reliable, and performed well. I want to fix my issues and get back to enjoying my car. I also want to be sure these parts will fit like stock, and be compatible with my stock powdercoated turbo cover. Am I making the right decision? Thanks for any input. James-
 
Why not have your unit refreshed with seals n bearings? You know it fits, and what it can do. Unless you have money to throw at the new stuff.
 
I've asked a reputable Forum Member twice for a price to rebuild, and he didn't seem interested. But yes, I have the money for new parts. Also Full throttle says 2-3 weeks for delivery on new turbo, and I feel that's probably quicker than a rebuild.
 
PT 5831 = T31
The T31 turbine is old school used on many turbos like the TA49, TE44 and many more. A 5831 or maybe better a 5931 will outflow by a little bit the 44/49.
The PT5858 uses newer compressor and turbine wheels, it works well. It is better than the 44/49.
Have you contacted Bison?
 
"I've asked a reputable Forum Member twice."

I'm only guessing, but I think that might just be Bison.

I asked him to rebuild a Precision 67/66 some time back and he wanted nothing to do with it. NOTHING.

He's great, don't get me wrong. He's THE GURU. However, he can pick and choose his work, after all, it's HIS business, and again, proprietary stuff often gets in the way of the independent guy, he doesn't need that kind of bullshit.

But I could be wrong........ Wouldn't be the first time........:)
 
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The T31 turbine is old school used on many turbos like the TA49, TE44 and many more. A 5831 or maybe better a 5931 will outflow by a little bit the 44/49.
The PT5858 uses newer compressor and turbine wheels, it works well. It is better than the 44/49.
Have you contacted Bison?
Yes I have. Thank you for the feedback.
 
"I've asked a reputable Forum Member twice."

I'm only guessing, but I think that might just be Bison.

I asked him to rebuild a Precision 67/66 some time back and he wanted nothing to do with it. NOTHING.

He's great, don't get me wrong. He's THE GURU. However, he can pick and choose his work, after all, it's HIS business, and again, proprietary stuff often gets in the way of the independent guy, he doesn't need that kind of bullshit.

But I could be wrong........ Wouldn't be the first time........:)
You are not wrong.
 
Guys, I have been out of the game for a couple years, and have not driven my car in over 2 years. Other projects, stupid Covid, and life in general has gotten in the way. I want to buy a new turbo, new oil feed, and new oil drain for my car. Specs of the car are in my signature. If you can't see it because of a mobile device here it is.

1987 GN - 109 + .020 block / ARP rod bolts, head bolts & main studs / Weisco forged pistons / Comp 210-215 roller cam / Ported stocks / PT51 / RJC Power Plate / Lorenz boost controller / 3" THDP / Duttneck SLIC / 80lb. injectors / Walbro 340 & hotwire / Billet AFPR / TT 5.7 chip / AXIS / LS1 MAF / K&N 12" cone / Pypes 2.5" dual exhaust / D5 / 3.42's / Spohn front UCA's / Hotchkis rear U & LCA's / QA1 coil overs (x 4) / 18's & 20's / S10 Blazer front brakes & cross drilled rotors / Aluminum rear drums & S10 rear cylinders / Jeep steering shaft / Alum. radiator / Intrepid dual fans

My old school PT51 is smokin like a steam train, and has gotten worse over the last couple years. My oil drain is completely clear and unobstructed, so I am assuming the turbo is leaking from the exhaust side. I'd like a newer style turbo, and I'm considering the Precision PT 5831 MFS w/ Buick .63 AR housing.

I would also like to purchase this new oil feed & return kit from GN1.

Would you guys agree with my decision? When comparing the specs from old PT 51 to new PT 5831 MFS they share the same HP rating of 585. They share the same inducer wheel size of 2.290" and they share the same exducer wheel size of 2.950". They also share the same inlet size of 3", and the same outlet size of 2". The main difference seems to be the wheel style PT 51 = T350 where as the PT 5831 = T31. Can I assume this is the difference between old school and new school??

I do not want to change my setup too much as my car has always been reliable, and performed well. I want to fix my issues and get back to enjoying my car. I also want to be sure these parts will fit like stock, and be compatible with my stock powdercoated turbo cover. Am I making the right decision? Thanks for any input. James-
Choose the turbo on the power you want to make
The d5 converter and piss poor turbo you have should be switched out and you could add alot of horsepower and torque for not alot of money.
Everything else is there
64mm and a converter change would be leaped and bounds once its tuned right.
Which the axis setup is fantastic
 
Choose the turbo on the power you want to make
The d5 converter and piss poor turbo you have should be switched out and you could add alot of horsepower and torque for not alot of money.
Everything else is there
64mm and a converter change would be leaped and bounds once its tuned right.
Which the axis setup is fantastic
Sound advice. I agree that the existing mods would support a larger turbo, as long as a matching converter was installed.
 
The T31 turbine is old school used on many turbos like the TA49, TE44 and many more. A 5831 or maybe better a 5931 will outflow by a little bit the 44/49.
The PT5858 uses newer compressor and turbine wheels, it works well. It is better than the 44/49.
Have you contacted Bison?
Im on Nigel side too I would add a little more $ and go with the newer exhaust wheel. it will make a little more power with less lag than your PT 51
Full Throttle also has a 6262 Same $ and you have more than enough cam fuel pump and injectors to to handle the extra HP and if your convertor worked with the 51 it should be a good match for a 6262.
 
My bad did not see D5 5858 would be best without a converter change. But its time to move up to a better converter regardless on turbo sulection.
 
Well, GS nats are happening this weekend. I would bet the guy has had a few things on the front burner getting ready for that.

That isn't to say a new unit with the new tech wouldn't be better. It comes with the expense of changing up the set up. Nothing wrong with that, just more money, and no one claims this activity is budget friendly.

Definitely price in a converter to get the most from those dollars spent on the turbo.
 
Well, GS nats are happening this weekend. I would bet the guy has had a few things on the front burner getting ready for that.

That isn't to say a new unit with the new tech wouldn't be better. It comes with the expense of changing up the set up. Nothing wrong with that, just more money, and no one claims this activity is budget friendly.

Definitely price in a converter to get the most from those dollars spent on the turbo.
Thank you Rich!
 
Husek 3021 converter, 6062,6262,6266
Researching the 6262 with E cover ( to work with my existing setup ), and a #3021 converter. Is the #3021 converter a 2800 or 3000, or 3200 rpm stall ? I know, i know... depends on my setup.
 
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Researching the 6262 with E cover ( to work with my existing setup ), and a #3021 converter. Is the #3021 converter a 2800 or 3000, or 3200 rpm stall ? I know, i know... depends on my setup.
Tell Dave what you have and he builds to your combo.
 
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