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  • HKS [15-21 WRX STI / WRX S4] Super Turbo Muffler Ti - Titanium Finish - JDMuscleMufflershks31030-AF002

HKS

HKS

Super Turbo Muffler Ti - Titanium Finish

Fits: 15-21 WRX STI / WRX S4

$5,20000
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HKS Super Turbo Muffler Ti - Titanium Finish
Fits: 15-21 WRX STI / WRX S4

Fitment

Please Note: Fits 2015-2021 WRX STI (VAB) and 2015-2021 WRX S4 (VAG) — HKS Super Turbo Muffler Ti, titanium muffler assembly (titanium construction and finish). HKS part number 31030-AF002 (from variant SKU hks31030-AF002; no part number was in the legacy title). Buckets: 2015-2017, 2018-2021 Subaru | WRX STI. WRX S4 coverage recorded here (no WRX S4 bucket exists). Title retitled: legacy "[15-21 WRX STI / 15-21 WRX S4]" normalized to [15-21 WRX STI / WRX S4] per model-naming rule. Fitment and specs are distributor-sourced — official HKS verification pending (flagged for final sweep). ZERO-IMAGE FLAG: no images attached — official HKS imagery not attached via API in this pass; flagged for Leo's media sweep. $5,200.00, no sale (compare-at equals price).
  • 2015–2021 Subaru | WRX STI

Description

The HKS Super Turbo Muffler Ti is a titanium muffler assembly for 2015-2021 Subaru WRX STI (VAB) and WRX S4 (VAG) applications, combining a high-flow muffler design with HKS engineering for performance-oriented exhaust systems. Its titanium construction reduces weight while delivering a refined, purposeful exhaust presentation with a distinctive titanium finish. Supplied as one muffler assembly; confirm compatibility with the vehicle's existing exhaust configuration before ordering. Professional installation is recommended.

  • HKS part number 31030-AF002
  • Vehicle-specific fitment: 2015-2021 WRX STI (VAB) and 2015-2021 WRX S4 (VAG)
  • Super Turbo Muffler design engineered by HKS for performance-oriented exhaust applications
  • Titanium construction and finish for reduced weight and enhanced appearance
  • Application-specific construction for VAB / VAG chassis exhaust systems
  • Not CARB approved — review applicable emissions requirements before installation or use

Shipping and Delivery

Review our Shipping Policy for delivery details, shipping costs and exclusions.

Warranty and Support

For HKS warranty information, contact our support team.

Return and Refund

Eligibility, exclusions, applicable fees and exceptions are detailed in our Return Policy. Restrictions apply to special-order and custom products.

Proposition 65

Proposition 65 Warnings: cancer and reproductive harm www.p65warnings.ca.gov