Precision vs. Garrett A/R .63 exhaust housing

[benoitthegr8]

The pics below are of a Garrett (the smaller ) and a Precision ex-housing, both from TE44/PTE44's. I had read on the board in here somewhere that the .63 housing was preferable to the .82, and of the .63 housings that the precision was capable of more power. I bought the precision housing from a guy in the board, when I compared them I could not believe the size difference. I even pm'd him to make sure he sent me the right housing. I'm curious as to why there would be such a dramatic difference in the size, maybe Patrick could chime in....

Ben

 

[bison]

Its actually more than a .63. The photo shows it. My power but looser converter is required

 

[GNVYUS 1]

The AR is a measurement which can be achieved from different locations, so PTE's .63 is much bigger than Garrett's and is why everyone on here prefers them, more power.
http://www.turbobygarrett.com/turbo...ressor_housing_showing_A-R_characteristic.gif

 

[benoitthegr8]

Thanks for the link, that clears things up the measurment thing for my limilted knowledge on turbo chargers...

 

[bison]

The AR is a measurement which can be achieved from different locations, so PTE's .63 is much bigger than Garrett's and is why everyone on here prefers them, more power.
http://www.turbobygarrett.com/turbo...ressor_housing_showing_A-R_characteristic.gif

Yeah Garrett's is a .63. Precisions is more than .63 even though its cast as a .63.

 

[RUQWKNF]

Yes, the PTE housings are larger in external dimensions. I believe the main reasoning behind this was due to the fact, that the Garrett .63 A/R housings did not have enough material, to allow for machining for larger turbine wheels. This necessitated a larger casting, not only for size limitations, but also for availability issues. You have to remember, Garrett only made a limited number of 3 bolt .63 and .82 A/R turbine housings for the Buick applications. And I'm sure they stopped production on them back in the mid to late 90's. So, a decision was made to invest in a casting that was not only larger in diameter, but could be machined for pretty much all of the available turbine wheels at the time. Flow limitations of the stock Garrett housing was also a contributing factor in the design of the PTE casting. Sure it looks huge when compared side by side with a Garrett, but in reality, it's what is inside that counts. Eventhough it says .63, it might be closer to .65 A/R, maybe more, but until someone actually shells out the high price to have one flowed by Garrett we won't really know. And to my knowledge, no flow tests were ever done, or if they were done, they were never published by PTE. I never saw any info during my time there.

Just for the record, the .63 A/R PTE housing for a TE-44 turbo, should have part number THB3-31 CNC cut into the downpipe face of the housing.

HTH


Patrick

 

[Super6]

i had a .63 precision on my te44 and a buddy of mine had a .63 garrett on his te60. the precision was much bigger. i ran a stock d-5 torque converter with it and the spool was instant. it was impressive up top..........Bob

 

[benoitthegr8]

It's interesting that Garrets .63 Housing inside in not all that smaller than the Precision housing. The precision housing definately has more meat around the casting. The entire reason I was replacing the Garret housing was because there are two cracks on the inside of the housing. one inside the exit port almost half way up to the 3 bolt flange. And the other in the certer where the housing transitions into the exit port, exactly with the casting centerline. I wonder if this was a known flaw in the housing, and that Precision looked to correct the problem with the Exhaust housing by casting it larger?

 

[Toady]

The entire reason I was replacing the Garret housing was because there are two cracks on the inside of the housing. one inside the exit port almost half way up to the 3 bolt flange.

Years ago I bought a rebuilt stock turbo off the board and pulled the exhaust housing to have it coated. It was cracked, and I called John Craig about it. He told me that "they all crack" and not to worry about it.

 

[ReaL99]

Year's ago I bought a TE-44 Turbo with the Precision .63 Housing.I swapped Housing's for a Garrett plus some cash to a board member.That Precision .63 is alot better on the street and track for my car.I may be getting a BB 61 Turbo next.