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Turbo Nomenclature

8K views 13 replies 10 participants last post by  rxc224 
#1 ·
Is there any resource out there that has what all the various nomenclature associated with the different tubos means or stands for? For instance, everyone know that 67 would be 67 mm, but what about turbos like the HKS 2835 twins? or how about the GT47-88? There's a lot more out there I know, I'm just curious. Then there's prefixes and suffixes... GT, PTE, GTS, GTQ, etc... Help is appreciated, ridicule is welcome, but I'm hoping to get some productive replies as I try to expand my knowledge here. Thanks.
 
#2 ·
GT - Garrett Turbo
PTE - Precision Turbo & Engine
GTS - "S" turbine wheel in a GT frame
GTQ - "Q" turbine wheel in a GT frame

Turbonetics came out with what they called the "T" series many years ago. This is the nomencature you are familiar with (T67 = 67mm inducer). This is straight forward.

HKS2835 is a Garrett based turbo that has a GT28 sized turbine wheel with a GT35 sized compressor wheel (basically a GT2882).

Any Garrett turbo caries the naming convention of GTXXYY. The XX's define the turbine size, but this number is purely for reference and tells you almost nothing other than bigger is...bigger. Also, as it turns out, this number is roughly half that of the inducer diameter of the turbine wheel (GT28 has ~56mm inducer +/- a couple). It's a rough estimate. The YY's define the major diameter of the compressor wheel. So, a GT2882 has an 82mm compressor wheel. This 82mm is the exducer/major diameter (the big one). If you see an "R" added to the end it means ball bearing (GT2882R).

The GT47-88 is the aftermarket's way of trying to return to turbonetics nomenclature. It a GT47 turbo with a compressor wheel that has an 88mm inducer. In fact I believe it's actually a GT4708 (108mm compressor).

I hope that helps.

Daniel
 
#6 ·
I'm not real clear on the difference between the GTS and GTQ turbine wheels. I *think* they are either modified Garrett wheels or something from Turbonetics.

PTE does use primarily Garrett components. They cast a lof of thier own end housings and do some different wheel combinations.

Daniel
 
#8 ·
^^^Dude. Your sig is crazy. So is the reefer legal in Turkey? Must be nice.

Anyway, I belive the difference between the S and Q trim turbine wheels are the overall shape of the turbine with the S trim spooling a little bit faster than the Q. The S trim also does not sound as loud as the Q and you lose a lot of the cool spoolin' sound. At least, this is how it was explained to me.
 
#10 ·
As taken from garrett's website

GT Basics / Nomenclature

Today, Garrett has a wider selection of GT-series turbos available than ever before. As a result of this, please note that we have made a subtle modification to the GT nomenclature.

In our product catalog, all offerings are grouped according to their turbine wheel frame size. The frame size of a turbo or CHRA is dictated by its turbine wheel inducer diameter . The larger the turbine inducer, the bigger the frame size-- so any turbo in the GT42 family has a larger turbine wheel inducer than those in the GT35 family, and so on.

In the model name of each turbo or CHRA, you'll also notice two digits after the frame size. These two digits refer to the compressor exducer diameter, as measured in millimeters.

Let's use the GT4294 as an example. This unit has a GT42 frame size turbine coupled to a 94mm (exducer diameter) compressor wheel.

If there's an "R" on the end of a model name, this means the unit is ball bearing. So, a GT4294 is not ball bearing; whereas a GT4294R is ball bearing.

The biggest change related to the nomenclature is this: units which utilize a 53mm turbine wheel (as measured at the inducer) are now referred to as "GT25" frame size, while units employing the slightly larger 53.85mm turbine wheel are now referred to as "GT28" frame size.

For those familiar with our product range, this means that the unit formerly known as "the GT28R" (part number 466541-1) is now in the GT25R family. More specifically, it is now a GT2560R model.

A Guide To Garrett’s "GT" Model Numbers

GTxxyyzz:

* Positions "xx" refers to the frame size of the turbine wheel inducer.
o For example the "GT28" in "GT2860RS" refers to its turbine wheel frame size family. All GT28 units use a turbine wheel with 53.85mm inducer diameter
o As a rule of thumb, the larger the number, the larger the turbine wheel.
* Positions "yy" designate the compressor wheel exducer (major) diameter in millimeters
o The "60" in the GT2860RS example above has a 60mm compressor wheel exducer diameter.
o Note: Wheel sizes 100mm and over omit the "1" (hundreds digit)
o Example: the 02 in a GT4202 refers to its 102mm compressor wheel exducer diameter
* Positions "zz" may be used to designate special features of a particular turbocharger where applicable
o Example: GT2860RS
o "R" = this is a Ball Bearing unit
o "S" = used for units which require some differentiation from units in the same family
Compare a GT2860R to a GT2860RS. While both are ball bearing and externally similar, the GT2860RS is better suited for higher-flow applications than the GT2860R. In this case, the S reflects the higher-flowing nature of the GT2860RS
More turbo info can be found here http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_tech101.html
including what trims are... what A/R is... how compressor maps work... etc...
 
#12 ·
67 = inducer (small diameter).

Inducer = flow entry
Exducer = flow exit

Garrett's GT4094R is actually 56 trim and has a ~71mm inlet.

Daniel

**edit**
I was thinking of the GT4294R. The 4094 is smaller trim (same wheel though) and about 67mm. This is a pretty new turbo though. Typical 67mm turbos have used a larger trim version of a smaller wheel.
 
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