Many modern sports cars derive a large boost to their performance by utilizing a turbocharger. Turbochargers are essentially gas compressors that provide forced induction, thus increasing engine power. IHI is a manufacturer that produces a number of different turbochargers, including the VF34, which is used in the Japanese market Subaru WRX STI "RA" version. It is also a very popular direct replacement turbocharger for tuners to utilize. The VF34 has the same specifications as the VF30, however utilizes a roller bearing instead of a bronze bearing.
The VF series of turbochargers have the same water-cooled core assembly and vary by the wheels and housing. The differences in these variables alter the flow, and thus the additional performance offered by these turbochargers. The VF34 is standard equipment on JDM version seven Subaru Impreza WRX STi Spec-C.
The VF34 turbocharger has a compressor inlet diameter of 47.9 centimeters and a compressor housing nominal rating of C. The compressor has six blades. The turbine housing is a 9.4 PZ18-H with a 94001 turbine that has eleven blades.
The VF34 turbocharger utilizes a P18 exhaust housing. VF34s have a C484 waste gate actuator. Turbine casting ID and batch numbers are as follows: S4, H, IC F55. VF34s are direct bolt on units.
The VF34 is rated at 460 cfm (cubic feet per minute) at 18 psi (pounds per square inch). Expected horsepower is 325-375 provided the car has an upgraded fuel pump, adequate fuel management and upgraded fuel injectors.
