SKU: HS15SW4GTT
Invidia 2015-2021 Subaru WRX/STI Single N1 Titanium Tip Cat-back Exhaust
The Invidia HS15SW4GTT cat-back exhaust system bolts onto 2015-2021 Subaru WRX and STI models for immediate performance upgrades. This full cat-back replaces the stock section after the catalytic converter with 3-inch mandrel-bent T304 stainless steel piping and a single N1 titanium burnt tip. Drivers gain 8-12 wheel horsepower, sharper throttle response, and a refined deep exhaust tone that enhances every drive.
Key Features
- T304 Stainless Steel Piping: 76mm diameter mandrel-bent tubes ensure smooth exhaust flow, reduce backpressure, and resist corrosion for long-term durability.
- Single N1 Titanium Tip: 102mm burnt titanium finish adds distinctive style and heat resistance while directing a focused exhaust note.
- Lightweight Design: Weighs 24 lbs, shedding over 12 lbs from stock for better handling, acceleration, and fuel efficiency.
- Double Wall Tip Construction: Provides premium appearance and sound insulation for a balanced aggressive tone inside and out.
- Bolt-On Fitment: Direct replacement using factory mounts retains catalytic converter compliance and simplifies upgrade process.
Product Notes
- Retains all factory emissions components for straightforward smog testing.
- Dyno-tested gains of 8-12 whp and 10-15 ft-lbs torque across RPM range.
- Large shipping box measures 52 x 14 x 14 inches with protective padding.
Installation Notes
- Professional installation recommended.
- Bolt-on system requires no welding or cutting of factory components.
- Compatible with factory hangers, clamps, and resonators included.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2015-2021 | Subaru | WRX | Base |
| 2015-2021 | Subaru | WRX | Limited |
| 2015-2021 | Subaru | WRX | Premium |
| 2015-2021 | Subaru | WRX STI | Base |
| 2015 | Subaru | WRX STI | Launch Edition |
| 2015-2021 | Subaru | WRX STI | Limited |
| 2016 | Subaru | WRX STI | Series.HyperBlue |
Why Choose Invidia?
- Japanese engineering delivers precise fitment and reliable power delivery.
- T304 stainless steel piping withstands extreme heat and road conditions.
- Proven dyno results and motorsport heritage back every system.
Frequently Asked Questions
- Q: Will HS15SW4GTT fit 2017-2021 WRX/STI models?
A: Yes, confirmed direct bolt-on fitment for all 2015-2021 Subaru WRX and STI trims including base, premium, limited, and special editions. - Q: What is the tip material and size?
A: Single N1-style tip uses genuine titanium with burnt finish, measuring 93mm inner diameter by 102mm outer for bold presence. - Q: What warranty covers this exhaust?
A: Invidia offers limited lifetime warranty against manufacturing defects when installed by certified shop.
Shipping & Handling
- Method: UPS or FedEx Ground
- Availability: In stock – ships same or next business day
- Packaging: Secure oversized box 52 x 14 x 14 inches
- Weight: 24 lbs product, 35 lbs shipping





Reviews
There are no reviews yet.