Tag Archives: exhaust housing

89 – 02 12v & 24v HX35 HX40 67mm Turbine Housing & Wheel Upgrade

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HX35 64mm x 76mm turbine Wheel and exhaust housing upgrade.
Please Read Carefully: This Housing is made to directly fit 1989 1997 24v turbochargers as a upgrade.  To work on other models modification is need as listed below:

1989-1997, have some variations of the factory turbo charger, this turbine housing and wheel work as an upgrade to the H1C and HX35, even though there are different version, in which some did not include wastegate actuators, this housing is still a direct fit on the factory turbo chargers in combination of using the turbine wheel included. This kit is intended to be used with a compressor upgrade 60mm, 62.45mm, or 67mm.

The turbine housing in this listing has 4 drilled through holes at the t3 flange, because the 12v engines use 4 studs threaded into the manifold. The 24v cummins (98- 02) has 2 threaded holes on the turbine housing and 2 threaded holes on the manifold to use studs. If this housing is used on a 24v cummins, 2 bolts and nuts will need to be used to bolt on the turbine housing because the exhaust manifold and turbine housing is not threaded for studs and the manifold is only threaded for 2 studs. If you are using this kit on a 24v you will not need to use the factory 24v wastegate actuator and mount on the compressor housing.

–If you are using this turbine housing on a 12v turbo with a horizontal mounting wastegate actuator, no actuator, or vertical wastegate actuator, this is a direct fit.

Modifications Required to fit 12v model turbos: (there are 2 versions of 12v Engines)

-To fit 12v turbos normally using horizontally mounted actuators, the threaded holes must be drill on the t3 flange for the manifold studs to go through the turbine housing. (thats it!)

–Some 12v models cannot use the horizontal actuators because they interfere with the oil drain which won’t allow the turbo to bolt on. However, the vertical mounting wastegate actuator is universal, there for this turbine housing upgrade is a universal fit for both model 12v engines.

Details of the listed items:

Upgrade for the 12v & 24v 5.9 cummins

Includes:

  • Fits 1989 – 2002 12v & 24v cummins factory HX35 turbo as upgrade
  • Direct fit for 1989 – 1997 12 valve turbo chargers / engines
  • 2 bolt and nuts are needed to fit 1998 – 2002 24v because no threaded holes on t3 flange (no threads for studs)
  • HX40 67mm x 76mm turbine shaft
  • HX35 turbine housing machined to HX40 67mm x 76mm turbine
  • 5 bolts
  • 5 bolt flanged machined to the 67mm x 76mm turbine
  • 5 bolt downpipe gasket
  • The Wastegate orientation is mounted on the compressor housing.
  • Wastegate not included.
  • Recommended to use this turbine housing with HX40 60 x 86 or 62.45 x 86 billet compressor wheel
  • Condition is New
Click here to buy this item from our Ebay listing

98 – 02 24v HX35 HX40 64mm Exhaust Housing Upgrade

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HX35 64mm x 76mm turbine Wheel and exhaust housing upgrade.
Please Read Carefully: This Housing is made to directly fit 1998 -2002 24v turbochargers as a upgrade. To work on other models modification is need as listed below:

Modifications Required to fit 12v model turbos: (there are 2 versions of 12v Engines)

-To fit 12v turbos normally using horizontally mounted actuators, the threaded holes must be drill on the t3 flange for the manifold studs to go through the turbine housing. (thats it!)

-To fit 12v turbos normally using vertically mounted actuators, the threaded holes must be drill on the t3 flange for the manifold studs to go through the turbine housing, and the wastegate arm must be repositioned to operated vertically rather than horizontally. The arm must be cut off and rewelded. (Some 12v models cannot use the horizontal actuators because they interfere with the oil drain which won’t allow the turbo to bolt on. 

Explanation of the fitment Modification:

This is a custom made housing, the t3 divided flange is threaded for 2 studs for the purpose of bolting onto an HX35 Dodge ram 1998.5 – 2002 24v exhaust manifold. If you want to use this with a 1989 -1998 12v manifold, the threaded holes will have to be drilled out larger on this turbine housing for the 12v manifold studs to allow the turbine housing to bolt on. (The 12v Exhaust manifolds have 4 threaded holes for studs on the manifold).  In addition, this turbine housing is designed to be used with wastegate mounted to a 24v 1998-2002 compressor housing or you can use a 12v horizontal mounting wastegate actuator + mounting hardware, but only on 24v engines or 12v engines where the horizontal actuator wont interfere with the oil drain. 

This turbine housing’s wastegate arm can be repositioned (cut off rewelded) to work with vertically mounted wastegate actuators, but not every 12 valve engine will allow a horizontal actuator to bolt on because the oil drain on some 12 valve engines will be in the way not allowing the horizontal actuator and turbo to bolt on. In summary some 12v engines can use a horizontal mounting wastegate actuator & Turbine housing and some cannot, but the turbine housing’s wastegate arm’s position can be changed to work with a vertical or horizontal mounting wastegate actuator, but you must have the matching wastegate actuator and mounting hardware. At the time of this writing, i only have the vertical mounting wastegate + hardware. 

Details of the listed items:

Upgrade for the 24v 5.9.

Includes:

  • Fits 1998 – 2002 24v cummins factory hx35 turbo as upgrade
  • Hx40 64mm x 76mm turbine shaft
  • Hx35 turbine housing machined to hx40 64mm x 76mm turbine
  • 5 bolts
  • 5 bolt flanged machined to the 64mm x 76mm turbine
  • 5 bolt downpipe gasket
  • The Wastegate orientation is mounted on the compressor housing.
  • Wastegate not included.
  • Recommended to use this turbine housing with HX40 60 x 86 or 62.45 x 86 billet compressor wheel
  • Condition is New
Click to buy HX35 turbine housing machined for HX40 64mm turbine wheel on Ebay

This kit is intended to be used with a compressor upgrade 60mm, 62.45mm, or 67mm.

Choosing turbine housings

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turbine housing

Often when building custom turbos people will want to make a good deal of power and still have decent spool time. The best way to accomplish great spool up on a higher flowing turbo is to put a smaller turbine housing on it. A good example is taking a holset hx40 and replacing the factory .89 a/r housing and replacing it with a bep .55 a/r bep housing for a dsm.  The hx40 with the bep housing will be limited to 550-600 hp range instead of the 700 hp mark that people have made with the .89 a/r, but the spool time will increase which makes the turbo more streetable.  Another good example is having us machine a garrett t3 .63 a/r turbine housing to fit an hx35 or hx40. This will limit what this turbo is capable of flowing, but it will bring down the capable flow rates of the turbo down to size with a smaller engine to help spool time and over all efficiency. A good example is if you pair an hx35 with a 16 cm^2 turbine housing with a 2.0 liter 4 cylinder motor. If the car can ever spool that turbo up it will make huge amounts of power, but it wont start seeing boost until around 5,500 rpm in 3rd gear. If you had us machine a .63 a/r turbine housing for the same hx35, then the spool time will be moved to the 3,000-4000 rpm range depending on your boost level and it will still be capable of 450-500 hp.  The turbine housing choice that is best for your application depends on the displacement and number of cylinders of the engine that you are turbo charging.  Another deciding factor is what kind of power you are looking to make and drivability. When choosing a turbine housing you are sacrificing capable horsepower for spool time.

Often people will ask: should I go t4 or should I go t3 for my exhaust housing? This best way to answer this is by asking your self what kind of HP you want to make, and what kind of spool time you want to see. Also keep in mind the motor that you are using too. If its a 2.0 and your trying to make 450 awhp and you want to have decent spool time, I would recommend that you choose a t3 .63 a/r turbine housing or close. If you are turbocharging a 5.0 v8, the motor is naturally flowing 5 liters of air, so it makes sense that you need to used a larger turbine turbine housing in the t4 format to avoid choking the flow of the engine at higher rpm.  If you want decent spool time you want to put a turbo on the car that has flow rates close to the engine. If you use a turbo that flow less than the motor at 6500 rpm, then at 6500 rpm at wide open throttle you will feel the car stop pulling because the motor is having a hard time flowing more air because turbo turbo is limiting the flow. The fix for this would be to upgrade the turbine housing or the turbine wheel and compressor wheel. A good example is an evo 9 20g that we built that made 493 awhp, but the car choked at 6500. We never upgraded the turbine shaft of this turbo so the measurement were 52mm x 68mm for the compressor wheel and 49mm x 55.6mm for the turbine wheel. The reason the car was capable of 493whp, is because the turbine housing is twin scroll and 10.5 cm from the factory. If we wanted to help the car pull harder in the higher rpm range, we upgrade the turbine shaft to a tdo6h4R (58mm x 67mm) or tdo6sl2R turbine (54mm x 61mm). Though both turbines would help the turbo pull to redline, the tdo6sl2 turbine would be the best for spool time and the tdo6h4R turbine would be better for more power. The main reason why we upgrade the turbine wheels in most turbos that we build is because it is very limited for the turbine housing sizes for factory cars. In most cases there are no upgraded turbine housings, so we upgrade the turbine shafts as an alternative, which works better if your trying to retain some of your spool time.

There is not  a direct conversion for an A/R to cm^2 estimate but this chart works well for an estimate. 

Turbine housing

A/R to cm^2 estimate

6 cm2 = 0.41 A/R

7 cm2 = 0.49 A/R

8 cm2 = 0.57 A/R

9 cm2 = 0.65 A/R

10 cm2 = 0.73 A/R

11 cm2 = 0.81 A/R

12 cm2 = 0.89 A/R

14 cm2 = 0.97 A/R

15 cm2 = 1.05 A/R

16 cm2 = 1.13 A/R

17 cm2 = 1.29 A/R

19 cm2 = 1.37 A/R