The HKS Super Turbo Muffler is a JASMA-certified 75mm SUS304 stainless steel 2-piece cat-back (mid silencer and rear silencer) for the Subaru Impreza WRX STI GDB chassis variants E/F/G (EJ207, 2004-2007 four-door sedan), raising close-measurement sound from 84 dB stock to 91 dB with a single 124mm SUS304 tip.
| Type | Cat-back exhaust system (Super Turbo Muffler) — 2-piece (mid + rear silencer) |
| Material | SUS304 stainless steel |
| Pipe Diameter | 75mm |
| Tips | Single 124mm — SUS304 stainless steel |
| Sound Level | 91 dB (close, HKS); 84 dB stock |
| Part Number | 31029-AF001 |
Shipping: In-stock orders placed before 3 PM EST ship the same day, and everything else ships within 24 hours. Standard, expedited, and overnight options are available at checkout. Backordered items ship as soon as we get them back in stock. Contact us for lead times. See the full Shipping Policy.
Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
