The Turbo Landscape in Detail

Reply Subscribe

Thread Tools

Search this Thread

Jul 23, 2007 | 09:17 AM

#16

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

Bump for more info on my last two questions

Quote:

Garrett does not produce twin-scroll GT35R but Turbonetics does... does that mean Turbonetics casts a special turbine housing on their own?

Another question... why have I never heard of an Evo running a Turbonetics turbo?

And can someone explain to me.. the GT37R or I think what is called T67 P-Trim...

I believe this is a turbo from a company called Precision Turbo?

How specifically is this turbo developed? What is it derived from?

Jul 23, 2007 | 11:39 AM

#17

Steve@NoLimitmotors

Account Disabled

iTrader: (53)

Joined: Nov 2004

Posts: 610

Likes: 0

From: LI, NY

precision makes a turbo called the PT6776 P trim. It was used and tested by AMS and they worked out a deal to coin the name GT37R. There is no actual GT37R, but this PT67 that everyone calls a 37R. Its just a combination that precision put together and happens to work very very well

Jul 23, 2007 | 12:29 PM

#18

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

Hi Steve thanks for the info.

Is the PT67 a Garrett unit to start? What Garret parts do they start with. What is modified?

A brief look at Precision's website did not help me much. They seem to have a dozen model numbers "6776".

Jul 23, 2007 | 12:41 PM

#19

Ron

Evolving Member

Joined: Jan 2003

Posts: 152

Likes: 0

A PT67R is a T4 turbo. It has a 76 trim T4 turbine and a T04S compressor wheel with a 67mm inlet diameter. It uses a variety of compressor and turbine housings.

Breaking down the model name...
"PT" = Precision Turbo
"67" = 67mm inducer
"R" = ball bearing

I assume a PT67 (without the "R") is the same thing only using a non-ball bearing center section.

Today the only TRUE Garrett GT37R turbos are in their Cummins and Duramax diesel upgrade kits.

Jul 23, 2007 | 03:56 PM

#20

Geoff Raicer

Account Disabled

iTrader: (7)

Joined: Jan 2005

Posts: 1,344

Likes: 0

From: NJ / AZ FULL-RACE

Quote:

Originally Posted by crcain

And can someone explain to me.. the GT37R or I think what is called T67 P-Trim...

I believe this is a turbo from a company called Precision Turbo?

How specifically is this turbo developed? What is it derived from?

http://www.full-race.com/catalog/pro...b5e8caaa6f0285

this is our variation on the same turbo. It uses a p trim turbine wheel (76 trim 11 blades) and a 66.7mm 63 trim compressor wheel (84mm exducer, 6/12 blades)

generally, it is believed that the 10 bladed GT turbine wheels are more efficient, and the GT compressors (52-56 trim) are more efficient than the 63 trim compressor used here. GT turbos can be found at www.turbobygarrett.com

edit: i forgot to mention that the GT37R is almost the same turbo as the HKS T04Z, which is very popular in japan. i dont know why but the japanese prefer the HKS stuff to garrett GT turbos

Last edited by Geoff Raicer; Jul 23, 2007 at 03:59 PM.

Jul 25, 2007 | 09:00 AM

#21

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

Ok if we compared the PT67 to let's say the Garrett GT3582R.

The GT3582R is:

Turbine: T3 84 Trim with A/R choices (.63, .82, 1.06)
Compressor: 56 Trim with 61mm Inducer and 82mm Exducer with AR .70

Garrett says the "Whl Dia" of the turbine side is 68mm. I'm not sure if that means the inducer or exducer.

So now comparing this to the PT67...

The GT35R has a larger trim on the turbine side, but then a smaller housing T3 versus T4. I can't compare the size of the turbine wheels themselves as I'm unsure how to read this from the Garrett catalog.

The compressor of the GT35 is a 61mm inducer 56 trim. The PT67 is a 67mm inducer and I don't know its trim.

Anyway just speaking out loud here trying to make sense of how you understand the physical dimensions of these turbos. Maybe we can talk about compressor maps once I get a handle on this stuff?

Jul 25, 2007 | 09:10 AM

#22

Steve@NoLimitmotors

Account Disabled

iTrader: (53)

Joined: Nov 2004

Posts: 610

Likes: 0

From: LI, NY

Quote:

Originally Posted by Ron

pt6776 p trim comes in T3 as well

Jul 25, 2007 | 09:34 AM

#23

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

Can we find more info about the PT67 like the compressor trim, turbine inducer or exducer diameter, and then A/R options available?

Jul 25, 2007 | 10:15 AM

#24

Ron

Evolving Member

Joined: Jan 2003

Posts: 152

Likes: 0

The PT67R uses a T4 turbine wheel (which is a 74.2 mm wheel; or larger than a T3). This comes in a variety of T4 housings, and apparently T3 housings are available too. You'll have to call Precision for the details.

Its compressor wheel is an 84mm 63 trim T04S, same as the one Geoff is using above.

Again the PT67R (aka "GT37R", which completely misleading) is nothing more than a plain ol' T4. Not saying it's bad, just saying what it is. The BB aspect is nice.

While the GT3582R uses an 82mm 56 trim compressor wheel, it is not apples to apples based on dimensions. You have to consider the wheel aero itself, plus the effect of the housing. I wouldn't be surprised if the GT35R's flow potential was similar despite its smaller dimensions.

And then there is efficiency to consider....

Edit: I remembered that a T4 wheel is 74.2mm major diameter

Last edited by Ron; Jul 25, 2007 at 10:21 AM.

Jul 25, 2007 | 12:07 PM

#25

Ludikraut

Evolved Member

iTrader: (17)

Joined: Apr 2004

Posts: 6,224

Likes: 0

From: 41° 59' N, 87° 54' W

Quote:

Originally Posted by Full-Race Geoff

edit: i forgot to mention that the GT37R is almost the same turbo as the HKS T04Z, which is very popular in japan. i dont know why but the japanese prefer the HKS stuff to garrett GT turbos

Because, HKS =

(sorry, my way of subscribing to a good thread)

l8r)

Jul 25, 2007 | 09:57 PM

#26

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

This is what I've gleaned so far after doing a bit of math which I think is correct?

Code:

                     GT3582R     PT6776R

   Turbine Housing   T3          T4

   Turbine Inducer   68mm        74.2mm

      Turbine Trim   84          ???

   Turbine Exducer   40.8mm      ???

               A/R   3 options   ???

Compressor Exducer   81.5mm      84mm

   Compressor Trim   56          63

Compressor Inducer   61mm        66.6mm

      Ball Bearing   yes         yes

Jul 25, 2007 | 10:00 PM

#27

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

So when it comes to flow potential.. bigger is better in terms of wheel diameter. But given same wheel diameter, then larger trim means more flow potential too?

Jul 26, 2007 | 07:05 PM

#28

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

What does the term T3/T4 mean? Does it mean you are mating a larger compressor side with a relatively smaller T3 turbine housing?

What does the acronym "H.O." mean?

What does the part number "TO4R" refer to? What about "TO4S"? Are these Garrett par numbers for compressors?

What about "p-trim"? What does that mean?

Jul 26, 2007 | 07:31 PM

#29

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

What is wrong with my maths here?

From this URL:

http://www.turbobygarrett.com/turbob...o_tech102.html

I get the formula for exducer calculation to be:

Exducer = Inducer / squareroot(Trim / 100)

Is that correct? I can't believe how bad my algebra has gotten over the years!

Jul 26, 2007 | 07:31 PM

#30

crcain

Thread Starter

Evolved Member

Joined: Oct 2002

Posts: 2,788

Likes: 1

Update

Code:

                     Garrett     Precision  Full-Race   Garrett
                     GT3582R     PT6776R    FR T3/T67   GT3076R

   Turbine Housing   T3          T4         T3          T3

   Turbine Inducer   68mm        74.2mm     67mm        60mm

      Turbine Trim   84          ???        76          84

   Turbine Exducer   ???         ???        ???         

       Turbine A/R   3 options   ???        2 options   3 options

---------------------------------------------------------------

Compressor Exducer   81.5mm      84mm       84mm        76.2mm

   Compressor Trim   56          63         63          56

Compressor Inducer   61mm        66.6mm     66.7mm      57mm

    Compressor A/R   .70         ???        .70         .60

      Ball Bearing   yes         yes        yes         yes

Reply Share

First
Prev
2 / 4
Next
Last