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HKS Subaru Impreza GDB EF 04 / 06-07 - Stainless Steel Exhaust System - 75mm Silent Hi-Power T304 (31019-AF015)

The HKS Hi Power range of exhaust consist of different exhaust systems that all offer their own benefits depending on your needs.

This range of high performance exhaust systems from HKS has been carefully designed to improve flow rate and reduce back pressure whilst retaining road legal noise levels while maximizing high end power gains.

Silent Hi Power exhausts offer high performance and a sporty appearance with the added benefit of reduced noise levels, these systems are made of T304 grade stainless steel for high lustre and long lasting performance. They also introduced the silent chamber on certain models which removes alot of the lower frequency noise.

Hi Power 409 exhausts are a cost effective option, The rear section is made from SUS304 grade stainless steel while the non visible piping section is made from coated T409 which is more resistant to thermal expansion and has improved acoustic properties. This allows Hi Power 409 systems to have a straight through design without fear of excessive noise.

Hi Power Spec L exhausts are a light weight option that is half the weight of the stock system with a tip wrapped in carbon. Made of T304 it is super lightweight and has good over all performance.

Hi Power Spec R exhausts are 65% lighter than the stock system and being a one piece system reduce inefficiencies that can be found at the joints of stock systems. Made of titanium to ensure the system is lightweight and durable against weather.


  • Internal structure and piping path optimized for increased performance
  • Designed to reduce drone and unpleasant exhaust noise
  • JASMA standards compliant to ensure reasonable noise levels
  • Sound deadening Advantex glass wool used to muffle noise
  • SUS304 Stainless Steel Construction
Fitment & Specs 
Model GDB
Engine EJ20(TURBO)
Model Year 04/06 - 07/06


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