HKS Racing Ti Cat-Back Exhaust - Subaru WRX STI GD

Regular price $730.15 USD Sale price $730.15 USD Regular price $859.00 USD
Sale 15.0% $128.85 USD (15.0%)
Sold Out
SKU: hks31701-BF003
Product Description
HKS offers the Racing Muffler exhaust systems for high horsepower applications. Constructed of high-luster polished SUS304 stainless steel piping and a 170mm Titanium muffler assembly, the Racing Muffler is the lightest (40% lighter than the race inspired Hi-Power Exhaust system) and the highest flowing exhaust system HKS offers. The muffler utilizes a slip-on design that mates polished stainless steel piping and a lightweight titanium Muffler assembly. All Racing Muffler systems incorporate a 115mm-diameter tip and include a removable inner silencer for pit area use or for tracks that require a lower dB level. HKS Racing Muffler Systems are FOR OFF ROAD USE ONLY.

  • Subaru Impreza WRX [GD] (2002, 2003, 2004, 2005, 2006, 2007)
  • Subaru Impreza WRX STI [GD] (2004, 2005, 2006, 2007)


  • Titanium Tip and Muffler
  • SUS304 Stainless steel piping
  • Perfect mix of quality and affordability
  • 115mm tip with 74.7mm piping
  • Designed for USDM GD
  • Made in Japan

Extended Information

  • Type: Single Cat Back
  • Material: Titanium Muffler w/ SUS304 piping
  • Tip Diameter: 115mm
  • Piping Diameter: 74.7mm
  • Chassis: GD#
  • Engine: EJ20, EJ25
  • Idle Sound: 96dB (82 dB stock)

To provide faster delivery and turn around time; Kami Speed ships products out from different warehouses throughout the United States. Usually averaging 1-4 business days for processing prior to shipping.

Depending on the package, we ship using different carriers according to the item's location, content, and size.

Freight truck items, will require up to 7 business days to ship due to size. i.e. hoods, trunks, body kits, etc.

All orders made after 3:00pm ET will be shipped or processed the next business day.

Orders over $500 will ship insured and over $1,000 with signature and insurance in order to guarantee delivery. Orders over $1000 may not be able to ship to a different address not listed as the billing address or confirm payment address from the form of payment used. Orders with suite numbers, different billing, or apartment numbers will require signature if valued over $100.

All international orders outside of the USA are subject to duties and taxes fees per your countries jurisdiction and determined by customs.
Kami Speed serves the right to ship using an alternative method if we see it fit, in order to expedite shipping and reduce your rate depending on product value.

In stock, non special order items can be returned within 30 days of the product arriving to your house or place of work.
Returns will NOT be accepted on Clearance Items, Final Sales, Special Orders, Opened, Installed, Incomplete, or Otherwise Used Products. In order to initiate a return, an RMA number must be requested and approved via e-mail. All returns will be subject to a 20% restocking fee minus complete shipping cost (roundtrip).

Any processed orders that have not shipped will incur a 6% cancelation refund fee unless the product was not available to ship within a timely manner. No fee will be incurred if used as store credit.

For complete details on our return policy, please see our Help and FAQ link under HELPFUL INFO.

WARNING: Operating, servicing and maintaining a passenger vehicle or off-highway motor vehicle can expose you to chemicals including engine exhaust, carbon monoxide, phthalates, and lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. To minimize exposure, avoid breathing exhaust, do not idle the engine except as necessary, service your vehicle in a well-ventilated area and wear gloves or wash your hands frequently when servicing your vehicle. For more information go to

Customer Reviews

Based on 1 review
vividwrx13 (Phoenix, AZ, US)

Another quality piece from HKS.. Exhuast fit perfect and included everything needed for install (i.e. gaskets and hardware) Sounds amazing, looks even better... cant go wrong with HKS