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Info: VF Series turbo
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Old 14 Mar 2007, 01:51 PM   #1 (permalink)
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Info: VF Series turbo

The VF series (VF22, VF23, VF24, VF29, VF30, VF34, VF39) are the most common direct replacement turbos. All VF-series turbochargers use the same roller bearing, water-cooled core assembly. The differences are in their wheels and housings to achieve different flows.

The VF22 has the largest potential for peak horsepower. In other words, in the IHI model range, the VF 22 supports the highest boost levels. It is capable of running up to 25 psi. Because it is a roller bearing turbo, turbo lag is minimal...the boost comes on around 3300 rpm. Expect to max out the VF22 somewhere in the 400-450 hp range.

The VF23 starts the middle ground. It comes on boost around 3100 rpm and is capable of running 20 psi of boost. Expect to max out the VF23 somewhere in the 300-350 hp range.

The VF 24 starts to come on around 2900 rpm and will significantly improve power through the midrange over the stock TD04 turbo. However, the VF 24 is only capable of running around 17 psi.

The VF23 and VF 24 are a great replacement for those who value drivability higher than maximum power.

The VF29 & VF30 delivers a very wide increase in torque over the standard TD-series turbos.

The VF 30 is a fairly new IHI model that utilizes the exhaust housing of a VF24 and the compressor housing sized between a VF 23 and a VF 22. It comes on boost down low (around the 3000 rpm range). With upgraded injectors, fuel pump, and engine management, the VF 30 is good for 365-390 horsepower. It is important to note that the VF30 is NOT a roller bearing turbo.

The IHI VF34 (which comes standard in the Japanese market STi version "RA") is a new roller bearing turbo. It has the same specifications (compressor size, etc.) as the VF 30. The difference lies in the roller bearing which, theoretically, allows quicker spool and better response. It costs a couple hundres more than a VF 30. The VF 34 maxes out around 365-390 hp. It is probably the most popular option for big turbos on the WRX.

One other turbo to note is the VF 39...it comes standard in the USDM STi. While we don't have all the specs yet, these are a new roller bearing, TWIN SCROLL design. Performance numbers are pretty similar to the VF34...maxing out just under 400 hp.

A new high performance modified IHI turbo has made its way to the market recently. They are the Power Enterprises PE 1818 and the 1820. The 1818 supposedly comes on boost extremely fast...which make it great for road racing or aggressive driving (remember to be responsible :^). The 1818 maxes out somewhere between 350-375 hp.

The 1820 is larger than the 1818 and is capable of running more boost, but at the expense of more turbo lag. Expect it not attain full boost until you have passed 4000 rpm. However, it can be tuned to 400+ hp.
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Old 07 May 2007, 10:33 AM   #2 (permalink)
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More info on the VF series.



VF22

This turbo has the highest output potential of all of the IHI VF series turbos and is the best choice for those who are looking for loads of top end power. The top end power however, does not come without a cost. The VF22 spools significantly slower than the rest of the IHI models due to the larger P20 exhaust housing and is much less suited for daily driving than some of the other models. Although the largest VF series turbo, the VF22 is not quite optimal for stroked engines or those who wish to run more than 20PSI of boost.


VF23

The VF23 is considered a great all-around turbo. Like the VF22 it utilizes the largest P20 exhaust housing. This housing is mated with a smaller compressor housing of the of the VF24. This turbo is considered optimal in applications with range from mild to slightly wild. It does not have the same top end power of the VF22, but spools up significantly quicker.


VF24

This turbo shares its compressor housing with the VF23 however, this housing is mated with a smaller (P18) exhaust side. The smaller characteristics of this turbo allow it to provide ample bottom end power and quick spool. This turbo is very popular for Imprezas with automatic transmissions and Group N rally cars.


VF28

VF28 came standard on the STi Version 5. In terms of overall size, it is smaller than the VF22, VF30 and VF34, and about same size as the VF23. The VF28 features a ball bearing center section.



VF29

This Turbo is nearly identical to the VF24, with the same compressor and exhaust housings. However the compressor wheel in the VF29 is has been changed slightly. The changes made to the compressor wheel in this model are generally viewed as improvements, and as such this unit is typically chosen over the VF24.


VF30

VF30 is commonly considered the best bang for the buck turbo in the IHI VF series line. A relatively new model the VF30 features the same exhaust housing as the VF24 but a larger compressor side similar to the VF22. The combination of these two parts results in increased output potential without the lag associated with the VF22. Although it doesn't offer the top end supremacy of the VF22, the VF30 is a great compromise between these unit and the quicker spooling models.


VF34

VF34 is nearly identical to the VF30, with the same exhaust housing and compressor. However the VF34 goes back to the ball bearing design, and in doing so achieves full boost approximately 500RPM sooner than the comparable VF30. The VF34 is the most recent IHI design and as such costs slightly more than its counterpart. Top end performance and maximum output are identical to the 30. As fitted to the newage WRX type UK.


VF35

VF35 has identical internals as the VF30 and it uses divided thrust bearings. However, the exhaust housing is a P15 which means this turbo will have fantastic spool characteristics. This turbo is standard on the new WRX Type RA. LIMITED SUPPLY. Also, on the newage STI type UK.


VF36

Roller bearing version of the twin scroll VF37, also has a titanium turbine and shaft for even quicker spool. Same compressor housing as VF30/34, however twin scroll P25 exhaust housing provides slightly better top end output due to reduced exhaust pulse interference. This turbo is good for 400HP and used on JDM STI Spec C from 2003 onwards.


VF37 (thrust bearing)
Enter the age of twin scroll IHI turbos. Same compressor housing as VF30/34, however has a new twin scroll P25 exhaust housing that provides slightly better top end output due to reduced exhaust pulse interference. Twin scroll also provides better spool up for improved low down response over the VF30/34. This turbo is good for 400HP and used on JDM STI from 2003 onwards.


VF38

Twin scroll turbo with titanium turbine and shaft. Smaller compressor housing than VF36/VF37 provides tremendous spool up capabilities but less top end than VF36/37. The spool capabilities of this turbo are demonstrated on the JDM Legacy GT, which reaches peak torque at 2400RPM.


VF39

Single scroll turbo used on USDM STI and latest 2.5L STIs released internationally. Smaller than VF30/VF34.


VF42
Exclusive turbo to the S203/S204 models, this features a twin scroll design with a slightly larger compressor than the VF36/37 turbos and different turbine design (more blades). The VF42 is a roller-bearing turbo and is likely of similar size to the VF22 turbo, but with twin scroll exhaust housing for faster spool and superior top end performance due to reduced exhaust pulse interference



VF43
This is the standard turbocharger used on the Euro STi MY06 and MY07 also standard on the MY07 USDM Subaru Impreza WRX STI. The VF43 has a thrust bearing design & has a larger wastegate than the VF39 designed to reduce boost creep issues.
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Last edited by 2002pete; 26 Aug 2009 at 07:47 PM.
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Old 15 Oct 2007, 11:55 PM   #3 (permalink)
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So at the very end, what is better a TD0516G or, a IHI VF 34?
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Old 25 Oct 2007, 09:08 PM   #4 (permalink)
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VF34 everytime ....!!!!!
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Old 30 Oct 2007, 01:47 PM   #5 (permalink)
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vf34 aint cheap, but does a very good job, tis whats on mine
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Old 31 Oct 2007, 06:35 PM   #6 (permalink)
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tbh I wouldn`t say they were that expensive though
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Old 05 Nov 2007, 01:31 PM   #7 (permalink)
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think new price no, but you don't find many second hand ones for sale thats for sure
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Old 08 Nov 2007, 10:32 PM   #8 (permalink)
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your not wrong there, new price is under £700 though, not sure exactly
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Old 09 Nov 2007, 12:13 PM   #9 (permalink)
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the only prices i found under 700 were just supplied prices, not fitted so be wary of that, cos they can be a ball ache to fit lol
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Old 09 Nov 2007, 03:31 PM   #10 (permalink)
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i know that mate and I`m not fitting it
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Old 25 Jan 2008, 09:45 PM   #11 (permalink)
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vf36 on my usdm 04 sti, oem sti exhaust made 315 awhp 372 ft/lbs to the ground with 100% methanol injection. My goals were to achieve quick acceleration, low lag, quick spool, and a wide powerband.
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Old 18 Sep 2008, 08:03 AM   #12 (permalink)
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Re: Info: VF Series turbo

great read
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Old 30 Nov 2008, 10:40 PM   #13 (permalink)
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Re: Info: VF Series turbo

hi can anyone tell which turbo is better the td04 or the td05. or shall i go for something completly different.
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Old 01 Dec 2008, 08:28 AM   #14 (permalink)
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Re: Info: VF Series turbo

Tbh not an expert, but from what I've read over the years it seems the TD05 will allow greater power gains and hold boost longer whilst the TD04 is a smaller turbo (iirc) and will therefore spool up a little quicker.
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Old 01 Dec 2008, 12:21 PM   #15 (permalink)
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Re: Info: VF Series turbo

thanks rikimaru, i only ask because i have a td05h turbo on my wrx now but i think its gone as theres oil in the heads. and i found a couple cheap tdo4l turbos for 50. or would you sugest a completly different turbo.
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