Twin Turbo T
New Member
- Joined
- Jan 22, 2003
Is a GT42 or GT42A garrett for a diesel the same has a gas turbo?
Gt42a?
- Thread starter Twin Turbo T
- Start date
- Joined
- May 26, 2001
On Garrett's official page, look underneath Large Frame turbos for the official listing of GT42 turbos that Garrett offers for gas burning racing applications. I'm sure this chassis size was originally designed for use in the diesel market, but they made sure to incorporate GT technology compressor and turbine wheels into the GT42 series of turbos. Meaning, these turbos listed on Garretts site are for high performance gas and or methanol racing applications.
TurboByGarrett.com - Turbochargers
They offer 2 journal bearing versions, and 2 dual ball bearing versions. The main differences between all the dual ball bearing versions are, each part number listed has a certain A/R turbine housing. Thus the 8 different part numbers for the dual ball bearing version. In Garrett speak, the two models are GT4292 (70mm inducer compressor wheel) and the GT4202. (74mm inducer compressor wheel) You will notice the R designation given to 8 of these part numbers, the letter R designates that it has a dual ball bearing oil and water center section. There are a couple of companies that will offer the GT4202 with a slightly larger compressor wheel. Precision offers a GT4276 version, which has a 76mm inducer compressor wheel, and others have offered this turbo with an even larger compressor wheel. One important thing about the out of box turbos from Garrett is, the GT4294 and GT4202 have a compressor wheel that screws onto the turbine wheel shaft. It does not bolt on. Therefore, it is of the utmost importance that you run a large enough blow off valve to support the hp level of the application. Especially on manual transmission applications. I have seen issues where the compressor wheel came unscrewed from the shaft and cause major carnage because the owner was not running a blow off valve. Typically this happened on rotary applications with manual transmissions and very high boost levels. The cure for that application, was to run two Tial 50mm blow off valves.
Hope some of this helps.
Patrick
TurboByGarrett.com - Turbochargers
They offer 2 journal bearing versions, and 2 dual ball bearing versions. The main differences between all the dual ball bearing versions are, each part number listed has a certain A/R turbine housing. Thus the 8 different part numbers for the dual ball bearing version. In Garrett speak, the two models are GT4292 (70mm inducer compressor wheel) and the GT4202. (74mm inducer compressor wheel) You will notice the R designation given to 8 of these part numbers, the letter R designates that it has a dual ball bearing oil and water center section. There are a couple of companies that will offer the GT4202 with a slightly larger compressor wheel. Precision offers a GT4276 version, which has a 76mm inducer compressor wheel, and others have offered this turbo with an even larger compressor wheel. One important thing about the out of box turbos from Garrett is, the GT4294 and GT4202 have a compressor wheel that screws onto the turbine wheel shaft. It does not bolt on. Therefore, it is of the utmost importance that you run a large enough blow off valve to support the hp level of the application. Especially on manual transmission applications. I have seen issues where the compressor wheel came unscrewed from the shaft and cause major carnage because the owner was not running a blow off valve. Typically this happened on rotary applications with manual transmissions and very high boost levels. The cure for that application, was to run two Tial 50mm blow off valves.
Hope some of this helps.
Patrick
JZ 97 SS 1500
Turbocharger Engineer
- Joined
- Jul 2, 2001
Two different units. Some of the GTA's used bolt-on covers as well as they were long shaft units. The current GT's use like Patrick said the stub shafts with screw on compressor wheels. Not the best design, but it works.....
