silent Hi-Power IMPREZA Explanation of the product Application chart

Code No. 31019-AF015

Cert. No. 03S04122

Model GDB
Engine EJ20(TURBO)
Model Year 04/06 - 07/06
Shape of muffler HP (TYPE-S)
(silent Hi-Power)
Main material S304(*2)
Diameter of tip 120
Diameter of center pipe 75(*3)
Close noise level Stock 84
HKS 92
About road clearance(*4) Clearance 135mm
Portion of the kit Center silencer
Product Weight


For applied model E, F. Fits to stock rear under skirt. Not tested for "STi SPEC-C", "SPEC-C WR-Limited 2004".


About HKS muffler

*1: About silencer shell type of Silent Hi-Power
TYPE-S/Oval silencer for noise reduction.
TYPE-H/Round silencer for performance.

*2: Main material in the component figure.

: SUS304/High quality stainless steel.
: SUH409/Stainless steel commonly used for stock exhaust.

*3: About center pipe
Diameter of center pipe is the portion that has the largest diameter. (Excluding silencer and tip.) It is the condition with stock suspension.

*4: Minimum road clearance between HKS muffler (Any parts included in the kit) and road surface. Therefore, it may be different from actual road clearance of the vehicle.
The data is basically the condition with stock suspension. However, please understand that some items have data with low down spring or ride height adjustable suspension kit.

Caution: Hook, bracket, stay may be changed without prior notice.

★ Exhaust noise level at idle.