SKU: 31006-BF001 | UPC: 4957266931752
HKS Hi-Power Muffler WRX STI 2015-2021 US
The HKS Hi-Power Muffler is a cat-back exhaust rear section built for 2015-2021 USDM Subaru WRX STI sedans. This SUS304 stainless steel muffler cuts weight improves exhaust flow and produces a deep aggressive tone for daily driving or track use. Drivers notice sharper throttle response stronger mid-range pull and a sportier sound without drone.
Key Features
- SUS304 Stainless Steel: Full construction from premium Japanese steel resists rust and withstands high heat for years of reliable performance.
- Weight Savings: 11.2kg unit drops 4.2kg over OEM muffler enhancing handling acceleration and overall vehicle dynamics.
- Deep Exhaust Note: 97dB output creates a refined powerful rumble that intensifies with revs ideal for STI enthusiasts.
- Power Increases: Dyno-proven +10PS gains boost torque and horsepower through smoother flow and reduced backpressure.
- Bolt-On Design: Mandrel-bent pipes (Ø80-90x2-60x2) with single right-rear 120mm rolled-edge tip ensure direct fit and clean styling.
Product Notes
- Confirm vehicle is USDM STI sedan prior to purchase for exact match.
- Inspect periodically and clean to preserve finish and flow efficiency.
- Boxed securely for protection during shipping and handling.
Installation Notes
- Professional installation recommended.
- Bolt-on replacement requires no welding or cutting of factory components.
- Includes all hangers gaskets and hardware for seamless mounting.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015-2021 | Subaru | WRX STI | Sedan USDM |
Why Choose HKS?
- Decades of JDM tuning expertise with Subaru OEM partnerships.
- Rigorous dyno and road testing for proven power and durability.
- Precise engineering matches STI chassis for perfect integration.
Frequently Asked Questions
-
Q: Does this muffler fit 2015-2021 WRX STI models?
A: Yes it bolts directly onto all USDM 2015-2021 Subaru WRX STI sedans with no modifications. -
Q: What materials and tip design are used?
A: SUS304 stainless steel piping and canister feature a single 120mm rolled-edge titanium-look tip on the right rear side. -
Q: What support comes with purchase?
A: HKS provides warranty coverage professional install advised and full hardware kit included.
Shipping & Handling
- Method: UPS Ground or FedEx Ground
- Availability: In stock - ships same or next business day
- Packaging: Sturdy box measuring 48 x 16 x 16 inches
- Weight: 24.7 lbs
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