IHI Series Specs

Alin

Diehard Car Enthusiast!
The VF series (VF22, VF23, VF24, VF29, VF30) 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 highes 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. It is important to note that the VF30 is not a roller bearing turbo.

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IHI Turbos

IHI VF10
This is the standard equipment turbocharger used on the USDM Legacy 4EAT MY91-94. No other information known at this time.

IHI VF11
This is the standard equipment turbocharger used on the USDM Legacy 5MT MY91-94. No other information known at this time.

IHI VF12
This is the standard equipment turbocharger used on the JDM Legacy RS MY89-93. No other information known at this time.

IHI VF13
This is the standard equipment primary turbocharger used on the JDM Legacy MY93-95. No other information known at this time.

IHI VF14
This is the standard equipment secondary turbocharger used on the JDM Legacy MY93-95. No other information known at this time.

IHI VF18
This is the standard equipment primary turbocharger used on the JDM Legacy MY96. No other information known at this time.

IHI VF19
This is the standard equipment secondary turbocharger used on the JDM Legacy MY96. No other information known at this time.

IHI VF20
This is the standard equipment turbocharger used on the JDM Legacy MY97. No other information known at this time.

IHI VF22
(490cfm at 18.0psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V3 Subaru Impreza WRX and optional on the JDM Subaru Impreza WRX STi 22b. Of all the IHI models, the VF22 has the largest potential for peak horsepower, and is capable of supporting the highest boost levels. It is capable of running up to 25 psi. The VF22 is a roller bearing turbo that utilizes the P20 exhaust housing.
Expect to achieve full boost with the proper mods and a quality tune between 3200-3700rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF23
(388cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM Subaru Impreza WRX STi 22b. The VF23 is a ball bearing turbocharger that utilizes the P20 exhaust housing like the VF22. This housing is mated with the smaller compressor housing of the VF24 for fast response and excellent low and mid-range performance. It does not have the same top end power of the VF22, but spools up slightly quicker.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF24
(425cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V4 Subaru Impreza WRX STi. 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.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF25
This is the standard equipment primary turbocharger used on the JDM Legacy B4. Utilizes a thrust-bearing design and a P12 exhaust housing. No other information known at this time.

IHI VF26
(400cfm at 18psi)
This is the standard equipment primary turbocharger used on the JDM Legacy B4. Utilizes a divided thrust-bearing design and a B14 exhaust housing. No other information known at this time.

IHI VF27
(420cfm at 18psi)
This is the standard equipment secondary turbocharger used on the JDM Legacy. Utilizes a ball-bearing design and a P18 exhaust housing. No other information known at this time.

IHI VF28
(425cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V5 Subaru Impreza WRX STi.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF29
(425cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger on the JDM V6 Subaru Impreza WRX STi. The VF29 is nearly identical to the VF24, with the same compressor and exhaust housings. However, the compressor wheel in the VF29 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. Has a different location for the pressure hose on the wastegate actuator.
Expect to achieve full boost with the proper mods and a quality tune between 2900-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF30
(460cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V7 Subaru Impreza WRX STi. The VF30 is a thrust-bearing turbo that utilizes the P18 exhaust housing of a VF24 and the compressor housing sized between a VF23 and a VF22.
Expect to achieve full boost with the proper mods and a quality tune between 3000-3500rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF31
Utilizes a P11 exhaust housing. No other information known at this time.

IHI VF32
This is the standard equipment primary turbocharger used on the JDM Legacy. It utilizes a ball-bearing design. No other information known at this time.

IHI VF33
This is the standard equipment primary turbocharger used on the JDM Legacy. It utilizes a P11 exhaust housing and a divided thrust-bearing design. No other information known at this time.

IHI VF34
(460cfm at 18psi, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM V7 Subaru Impreza WRX STi Spec-C. The VF34 is nearly identical to the VF30 but has improved spool up due to its roller bearing design. It also utilizes a P18 exhaust housing.
Expect to achieve full boost with the proper mods and a quality tune between 3000-3500rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF35
(425cfm, 250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the JDM Subaru Impreza WRX. The VF35 is similar to the VF34. It utilizes the same compressor housing and the same compressor inducer size. The differences are in the divided thrust-bearing design and the P15 exhaust housing. This allows the VF35 to spool slightly quicker than the VF34 at the cost of less top-end performance.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF36
(430cfm, 250-325whp, Modification Required)
This is the standard equipment turbocharger used on the JDM V8-V9 Subaru Impreza WRX STI Spec-C Type RA. The VF36 is a twin-scroll turbocharger that utilizes a ball bearing design, a P25 exhaust housing, and titanium aluminide (TiAl) compressor wheel for improved spool. It is essentially a fast spooling VF34.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF37
(430cfm, 250-325whp, Modification Required)
This is the standard equipment turbocharger used on the JDM V8-V9 Subaru Impreza WRX STI. The VF37 is a twin-scroll turbocharger that utilizes a thrust bearing design and a P25 exhaust housing. It is essentially a fast spooling VF30.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles.

IHI VF38
This is the standard equipment turbocharger used on the JDM Legacy MY04-06. The VF38 is a twin-scroll that utilizes a Titanium turbine and shaft. This turbocharger yields tremendous spool-up but offers less top-end than the VF36/VF37. The spool capabilities of this turbo are demonstrated on the JDM Legacy GT, which reaches peak torque at 2400RPM.

IHI VF39
(250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the USDM Subaru Impreza WRX STI. It can be found on all model years from 2004-2006. The VF39 utilizes a thrust bearing design and the P18 exhaust housing.
Expect to achieve full boost with the proper mods and a quality tune between 3000-3500rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles that utilize this turbo aftermarket. Though they are prone to cracking, VF39’s can be had for very cheap if bought used.

IHI VF40
This is the standard equipment turbocharger used on the USDM Subaru Legacy GT MY05-06.

IHI VF41
This is the standard equipment turbocharger used on the JDM Subaru Forester STI. It utilizes a P18 exhaust housing.

IHI VF42
This is the standard equipment turbocharger used on the JDM Subaru Impreza WRX STi S203 and S204. The VF42 features a twin-scroll design with a slightly larger compressor than the VF36/VF37 turbos and different turbine design (more blades). The VF42 is a roller-bearing turbo and is similar in size to the VF22 turbo, but the twin-scroll exhaust housing yields faster spool-up and a superior top-end.

IHI VF43
(250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the MY07 USDM Subaru Impreza WRX STI. It can be found on both base STI's and STI Limited's. The VF43 utilizes a thrust bearing design and the P18 exhaust housing. The primary difference between the VF43 and the VF39 used previously on STI's seems to be the stiffness of the wastegate. The VF43 has a stiffer wastegate designed to reduce boost creep issues.
Expect to achieve full boost with the proper mods and a quality tune between 3000-3500rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles that utilize this turbo aftermarket.

IHI VF44
This is the standard equipment turbocharger used on the JDM Legacy GT MY06. No other information known at this time. (Confirmation needed)

IHI VF45
This is the standard equipment turbocharger used on the JDM Legacy GT MY07. No other information known at this time. (Confirmation needed)

IHI VF46
This is the standard equipment turbocharger used on the USDM Subaru Legacy GT MY07. The VF46 utilizes a new five-arc scroll design to improve low and midrange performance over the previous VF40.

IHI VF48
(250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the USDM Subaru WRX STI MY08-10. The primary difference between the VF48 and the VF43 used previously on STI's is the more advanced bearing design.
Expect to achieve full boost with the proper mods and a quality tune between 3000-3500rpms. 2002-2005 WRX owners will need fuel upgrades for this turbocharger and proper engine management is highly recommended for all vehicles. This turbocharger is not a direct bolt-on for the MY08+ WRX.

IHI VF52
(250-325whp, Bolt-On)
This is the standard equipment turbocharger used on the USDM Subaru WRX MY09-10. This turbocharger is similar to the VF48 but utilizes the USDM Legacy GT-style housing.
Expect to achieve full boost with the proper mods and a quality tune between 2800-3300rpms. This is NOT a direct bolt-on for 2002-2007 WRX, but will fit the 2008 WRX and 2005+ Legacy GT without modification.

Mitsubishi TD04L-13T
(390cfm at 14.7psi, 200-275whp, Bolt-On)
This is the standard equipment turbocharger used on the USDM Subaru Impreza WRX MY02-07.
Expect to achieve full boost with the proper mods and a quality tune between 2500-3000rpms.

Mitsubishi TD04L-19T
(225-300+whp, Bolt-On)
This is the standard equipment turbocharger used on the USDM Subaru Impreza WRX MY08.
Expect to achieve full boost with the proper mods and a quality tune between 2500-3000rpms.

After the TD04
+500rpm lag on VF24/28/35
+600rpm lag on VF29
+650~700rpm lag on VF34
+800rpm lag on VF23/30
+900rpm lag on VF22

all on the same 3" exhaust after removing the TD04

All the turbo's with P18 exhaust housing & BB has good off boost response (VF28/34), and top end power of the 34 is very impressive , only down 3 odd kw on the 22 and yet heap more down low .

The VF30 starts late and come on fast , it has poor ish off boost response and very strong mid and top end .

The 30/34 & 35 have very good compressor wheels that work very efficiently and run lower intake temps and this is where the good power comes from .

The power on the 23 & 22 come from the open P20 exhaust housing, better exhaust flow and scavenging up top and the cost of some low to mid range power .

VF35 has identical internals to the VF30 and it uses divided thrust bearings. However, the exhaust housing is a P15 which sacrifices top end performance compared to the VF28/30/34's P18 exhaust housing.

The gains from the P18 exhaust housing is of better scavenging of the exhaust stroke in the top end , down side is the loss of low rpm torque as it allows fresh charge to exit the exhaust valves on cam over lap , much the same as what bigger cams do.

Summing that lot all up changing from a VF28 to a VF35 will give slightly (if any) more lag, but you will gain mid range power due to the more efficient (and slightly bigger) 6+6 bladed compressor wheel giving a cooler intake charge.

also
TD05/L TB, PZ?? - WRX MY94-96
TD04/L TB, PZ?? - WRX MY97-08

VF22 BB, PZ20 ex.h/48.5mm c.h/5b c.w/0.71 A/R - JDM MY97 V3 STi/1998/ optional 22B
VF23 BB, PZ20 ex.h/46.7mm c.h/6b c.w/0.71 A/R - JDM MY97 V3 STi/1998/ 22B
VF24 BB, PZ18 ex.h/46.7mm c.h/6b c.w/0.63 A/R - JDM MY98 V4 STi

VF25 TB, PZ12 ex.h/38.2mm c.h/10b c.w/0.36 A/R - JDM MY00 Legacy B4 Primary turbo
VF26 TB, PZ14 ex.h/38.2mm c.h/0.48 A/R - JDM Legacy B4 Primary turbo
VF27 BB, PZ18 ex.h/38.2mm c.h/10b c.w./0.63 A/R - JDM Legacy Secondary turbo

VF28 BB, PZ18 ex.h/46.7mm c.h/7b c.w/0.63 A/R - JDM/OZ MY99/00 V5/V6 STi
VF29 BB, PZ18 ex.h/46.7mm c.h/7b c.w/0.63 A/R - JDM WRX MY99-00 V5/V6 STi
VF30 TB, PZ18 ex.h/47.9mm c.h/6+6b c.w/0.63 A/R - JDM MY01 V7 STi

VF31 ??, PZ11 ex.h/??????
VF32 TB, PZ?? ex.h/46.5mm c.h/10b c.w/0.70 A/R - JDM/OZ Legacy/B4 Secondary turbo
VF33 TB, PZ11 ex.h/46.5mm c.h/6+6b c.w/0.75 A/R - JDM/OZ Legacy/B4 Primary turbo

VF34 BB, PZ18 ex.h/47.9mm c.h/6+6b c.w/0.63 A/R - JDM V7/V8 STi RA Spec C
VF35 TB, PZ15 ex.h/47.9mm c.h/9b c.w/0.51 A/R - OZ/UK MY02-05 STi
VF36 BB, twin-scroll titanium wheel/shaft - PZ25 ex.h/47.9mm c.h/9b c.w/0.63 A/R - JDM MY03-06 STi RA Spec C
VF37 TB, twin-scroll - PZ25 ex.h/47.9mm c.h/9b c.w/0.63 A/R - JDM MY03-06 STi
VF38 BB, twin-scroll titanium wheel/shaft - PZ?? - JDM/OZ MY05 Legacy/Liberty GT
VF39 TB, PZ18 ex.h/47.9mm c.h/9b c.w/0.63 A/R - US MY04-06 2.5L STi
VF40 TB, PZ17 ex.h - US MY05-07 Legacy GT/JDM Forester STi
VF41 ??, PZ18 ex.h - JDM Forester STi
VF42 BB, twin-scroll titanium wheel/shaft - PZ25 - JDM STi S203/204
VF43 TB, PZ18 ex.h/47.9mm c.h/9b c.w/0.63 A/R - OZ/US MY06-07 STi
VF48 TB, PZ?? - OZ/US MY08+ STi
VF52 TB, PZ?? - OZ/US MY09+ WRX

BB = Ball bearing
TB = Thrust bearing/Plain Sleeve bearing
ex.h = Exhaust housing
c.h = Compressor housing
(x)b = (x) bladed compressor wheel
c.w = Compressor wheel
A/R = Area to Radius turbine housing ratio
JDM = Japanese Domestic Model

PE 1818 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.

PE 1820 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.

IHI & Garret Turbo Specs
Model Type Compressor Inlet Diameter Compressor Housing Nominal Turbine Housing Turbine Approx A/R Compressor Wheel Blades Turbine Wheel Blades Waste Gate Actuator Turbine Casting ID & Batch
VF22 Roller Bearing 48.5 A 9.4 PZ20-H 94001 0.71 5 11 C395 H, H4
VF 23 Roller Bearing 46.7 B 9.4 PZ20-H 94001 0.71 6 11 C395 8psi TBA
VF 24 Roller Bearing 46.7 B 9.4 PZ18-H 94001 0.63 6 11 C418 8psi H, S4, 66
VF 30 Bronze Bearing 47.9 C 9.4 PZ18-H 94001 0.63 6 11 C484 H, S4, IC F55
VF 34 Roller Bearing

Garrett 400 Ball Bearing 53 - - Outlet Dia 51.5 - 7 9 11 psi
Garrett 450-500 Ball Bearing 53 Outlet Dia 46.9 - 7 10 14 psi

Turbo Type ----------- Approx flow @ pressure
Stock Turbo ---------- 360 CFM at 14.7 PSI
IHI VF 25 ------------- 370 CFM at 14.7 PSI
IHI VF 26 ------------- 390 CFM at 14.7 PSI
T3 60 trim ----------- 400 CFM at 14.7 PSI
IHI VF 27 ------------- 400 CFM at 14.7 PSI
IHI VF 24/28/29 ----- 410 CFM at 14.7 PSI
========= 422 CFM max flow for a 2 Liter at .85 VE pressure ratio 2.0 (14.7 PSI) 7000 RPM =======
IHI VF 23 ------------- 423 CFM at 14.7 PSI
FP STOCK HYBRID -- 430 CFM at 14.7 PSI
IHI VF-30 ------------- 435 CFM at 14.7 PSI
SR 30 ----------------- 435 CFM at 14.7 PSI
IHI VF-22 ------------ 440 CFM at 14.7 PSI
T04E 40 trim -------- 460 CFM at 14.7 PSI
========= 464 CFM max flow for a 2.2 Liter at .85 VE pressure ratio 2.0 (14.7 PSI) 7000 rpm =======
PE1818 -------------- 490 CFM at 14.7 PSI
Small 16G ------------ 505 CFM at 14.7 PSI
ION Spec (stg 0) --- 525 CFM at 14.7 PSI
========= 526 CFM max flow for a 2.5 Liter at .85 VE pressure ratio 2.0 (14.7 PSI) 7000 RPM =======
Large 16G ----------- 550 CFM at 14.7 PSI
SR 40 ----------------- 595 CFM at 14.7 PSI
18G ------------------- 600 CFM at 14.7 PSI
PE 1820 -------------- 630 CFM at 14.7 PSI
20G ------------------ 650 CFM at 14.7 PSI
SR 50 ---------------- 710 CFM at 14.7 PSI
GT-30 ---------------- 725 CFM at 14.7 PSI
60-1 ----------------- 725 CFM at 14.7 PSI
GT-35R -------------- 820 CFM at 14.7 PSI
T72 ------------------ 920 CFM at 14.7 PSI <--- Note you would have to spin a 2.0 L engine at about 14,000 rpm to flow this much air.
IHI VF 25 ----------- 395 CFM at 18 PSI
IHI VF 26 ----------- 400 CFM at 18 PSI
T3 60 trim ---------- 410 CFM at 20 PSI
IHI VF 27 ----------- 420 CFM at 18 PSI
IHI VF 24/28/29 -- 425 CFM at 18 PSI
IHI VF 23 ----------- 430 CFM at 18 PSI
IHI VF-30 ----------- 460 CFM at 18.0 PSI
AVO 320HP -------- 465 CFM at 17.5 PSI
T04E 40 trim ------ 465 CFM at 22 PSI
FP STOCK HYBRID- 490 CFM at 18.0 PSI
IHI VF-22 ---------- 490 CFM at 18.0 PSI
SR 30 --------------- 490 CFM at 22 PSI
Small 16G ---------- 490 CFM at 22 PSI
ION Spec (stg 0) - 500 CFM at 19 PSI
PE1818 ------------ 515 CFM at 22 PSI
Large 16G --------- 520 CFM at 22 PSI
========= 526 CFM max flow for a 2 Liter at .85 VE pressure ratio 2.5 (22 PSI) 7000 rpm =======
========= 578 CFM max flow for a 2.2 Liter at .85 VE pressure ratio 2.5 (22 PSI) 7000 rpm =======
HKS GT2835 ------- 580 CFM at 22 PSI 400 hp
MRT 400 ------------ 580 CFM at 16 PSI
AVO 400HP -------- 580 CFM at 17.5 PSI
MRT 450 ------------ 650 CFM at 19 PSI
AVO 450HP -------- 650 CFM at 20.0 PSI
SR 40 ---------------- 650 CFM at 22 PSI
========= 658 CFM max flow for a 2.5 Liter at .85 VE pressure ratio 2.5 (22 PSI) 7000 rpm =======
HKS GT3037 ------ 670 CFM at 22 PSI 460 hp
PE 1820 ----------- 680 CFM at 22 PSI
20G ---------------- 695 CFM at 20.0 PSI
HKS GT3040 ----- 710 CFM at 22 PSI 490 hp
AVO 500HP ------ 770 CFM at 22 PSI
SR 50 ------------- 770 CFM at 22 PSI
GT-30 ------------- 790 CFM at 22 PSI
60-1 --------------- 800 CFM at 22 PSI
HKS GT3240 ----- 830 CFM at 22 PSI 570 hp
GT-35R ----------- 880 CFM at 22 PSI
T72 --------------- 1000 CFM at 22 PSI <--- note you would have to run a 2.0 L engine at >40 PSI boost to flow this much air

Conversions used where there was control over conversion factors:
1 HP approx equals 1.45 CFM
1 CFM approx equals 0.0745 lb of air/min
0.108 Lb/min approx equals 1 hp
1 Meter cubed/sec = 35.314 CFS = 2118.867 CFM
1 KG/sec = 132 lbs/min approx equals 1771.812 CFM
power coversions:
1 PS = 0.9859 HP = 75 Kgf m/sec
1.3405 HP = 1 KW
1 HP = 746 watts

Sources:

http://www.dune-buggy.com/turbo/turbo.htm
http://www.gcg.com.au/technical/technical.html
http://www.ihi-turbo.com/turbo_RHE-RHF.htm
http://www.rb5286.pwp.blueyonder.co....rbo%20comp.htm
http://www.vividracing.com/turbodata.pdf
http://www.automotivearticles.com/Turbo_Selection.shtml
http://www.stealth316.com/2-3s-compflowmaps.htm
http://not2fast.wryday.com/turbo/maps
http://forums.nasioc.com/forums/showthread.php?t=1141476
 
Last edited:

Alin

Diehard Car Enthusiast!
Updated as of 12/25/14. :ty:
 

Batmobile_Engage

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