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The HKS 2021 Subaru WRX LEGAMAX Sport Exhaust is designed for the 2022-2025 Subaru WRX. Match manufacturer part number 31021-AF026, the complete vehicle or system configuration, dimensions, connections, and included components before ordering.
Key Features
- Performance exhaust component in the stated configuration
- Pipe diameter, routing, flange, gasket, and tip details are part-number specific
- Vehicle clearance and exhaust connection points must be confirmed
- Sound and emissions requirements vary by vehicle and location
Fitment
| Years | Make | Model | Application |
|---|---|---|---|
| 2022-2025 | Subaru | WRX | Confirm engine, body style, system configuration, and exact interface |
Specifications
| Brand | HKS |
|---|---|
| Manufacturer Part Number | 31021-AF026 |
| Product Type | Catback |
| Fitment Type | Vehicle Specific |
| Condition | New |
| Certification number | JQR60244002 |
| Main material | SUS304 / S304 stainless steel |
| Muffler shape | Ti-1 (Titan), LEGAMAX Sports |
| Tip outside diameter | 98 mm × 4 |
| Main pipe diameter | 74.7 mm → 60.5 mm × 2 → 45 mm × 4 |
| Close noise level, stock | 79 dB |
| Close noise level, HKS | 90 dB |
| Idling noise level, stock | 56 dB |
| Idling noise level, HKS | 63 dB |
| Minimum exhaust clearance | 130 mm. No change from stock front pipe clearance |
What's Included
One new HKS catback identified by manufacturer part number 31021-AF026, in the quantity stated by the title. Additional wiring, pipes, hoses, clamps, fittings, gaskets, fluids, tuning, tools, and installation hardware are included only when expressly listed for this exact part number.
About HKS
HKS develops exhaust, forced-induction, cooling, engine, electronics, and exterior components for import and performance vehicle applications.
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Frequently Asked Questions
How do I confirm this HKS exhaust part fits?
Match the manufacturer part number, listed year, make, and model, body style, engine, exhaust diameter, flange locations, and available underbody clearance.
Does this listing include every part needed for installation?
Only the items stated in the title and What’s Included section are supplied. Gaskets, adapters, hardware, hangers, or connecting pipes may be separate for some applications.
Will the exhaust change sound or require tuning?
Sound varies with the complete exhaust system and vehicle. Tuning requirements depend on the application, emissions equipment, and other modifications, so confirm with the vehicle tuner before installation.
Installation Instructions
Follow the current HKS instructions and the vehicle service manual for part number 31021-AF026. Compare every component, connection, dimension, and mounting point before disassembly. Use the correct tools, fasteners, torque values, fluids, wiring protection, and safety procedures, then inspect for leaks, interference, heat exposure, clearance, and secure operation before normal use.
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