Impreza 1997, (v4) onwards up to and incl 2004 with direct turbo inlet path only. Directly bolts to exhaust manifold as well as exhaust pipe off turbo. Minimal modifications required to fit. Best applications: This turbo is still the largest flowing IHI / STi Roller bearing turbo available and is a last option before a specialist turbo is chosen that may need to be larger. This is a popular replacement turbo for Impreza's instead of VF23, however with more modifications, such as exhaust and front mount intercooler, kits, etc. (designed for greater flow) as this turbo will start to come on boost start to come on boost at 3300