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Vivid Racing Gear Select the year of your Subaru STI:
HKS Silent Hi-Power Exhaust System - 31021-BF001
If you're a proud owner of a Subaru STI or WRX (2015-2021), the HKS Silent Hi-Power Exhaust System is designed just for you. This high-performance exhaust system not only enhances your vehicle's sound but also optimizes its overall performance.
Key Features:
- Muffler Shape: LM (LEGAMAX Premium)
- Main Material: SUS304 stainless steel for durability and corrosion resistance
- Tip Diameter: 90mm (Left and Right)
- Center Pipe Diameter: 75-69mm
- Noise Level: Stock - 82dB / HKS - 83dB (at idle)
Specifications:
The center pipe has a diameter that represents the largest section of the exhaust system, excluding the silencer and tip. The minimum road clearance between the HKS muffler and the road surface may vary depending on your vehicle's suspension setup.
Note that the data provided is based on stock suspension conditions, and some measurements may reflect vehicles with lowered springs or adjustable ride height suspension kits.
Caution: Components such as hooks, brackets, and stays may be subject to change without prior notice.
Fitment:
- Subaru STI 4D (2015-2021)
- Subaru WRX 4D (2015-2021)
Customer Feedback:
Users have praised the HKS Silent Hi-Power for its perfect balance of sound and performance. Many report a noticeable improvement in throttle response and a refined exhaust note that enhances their driving experience without being overly loud.
Watch It In Action:
Other Part Numbers:
HKS #hks31021-BF001
⚠ WARNING:
Cancer and Reproductive Harm
https://www.P65Warnings.ca.gov
| Make Vehicle | Model | Year |
|---|---|---|
|
2015-2021 Subaru STI |
STI | 2015-2021 |
|
2015-2021 Subaru WRX |
WRX | 2015-2021 |
Since its beginning, HKS has been committed to providing well-integrated, reliable,and environmentally sound performance systems. Mr. Hasegawa's strong leadership, engineering genius, creativity and willingness to listen to customers are the pillars of the company's success. Monitoring consumer reaction and input on issues pertaining to material quality, external appearance, sound quality, and of course, performance, HKS stays in tune with automotive enthusiasts' needs. Moreover, HKS' products are designed to be user friendly for easy installation.
HKS provides a warranty to the original purchaser of HKS exhaust systems against defects in materials and workmanship for a period of one year. The warranty applies only for vehicle specific exhaust systems. Other products such as metal catalyzers, front pipes, exhaust manifolds, and center pipes are not covered.
| Sale price | None |
| Wholesale price | $1,308.38 |
| Shipping |
Weight: 66.60 Length: 61 Width: 25 Height: 15 |
| Product Added At | Monday 12 December, 2022 |
| Product Modified At | Wednesday 06 August, 2025 |
| Imported By | ETLOverride |
| Last Edited By | Turn_API |
| View In Admin |
| Carb Approved | Yes |
|---|---|
| Carb Number | - |
| Epa Status | N/A |
| Prop65 | Unknown |
| Carb Required | - |
| Vendor | Inv | Cost | Retail | Jobber | Strict MAP | Core | Updated | |||
|---|---|---|---|---|---|---|---|---|---|---|
| Turn 14 | $1,108.80 | $1,540.00 | ? | $1,386.00 | ? | 2025-08-06 10:26:36 |
