2015-2021 Subaru STI Parts & Accessories

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  • APR 18 - 21 WRX/STI Performance Carbon Fiber Upper Canards | AB - 808028 - JDMuscleCanardsAPRAB-808028
    APR Performance

    Carbon Fiber Upper Canards

    Fits: 18-21 WRX STI

    $30500
    Pay over time · Est. $9.53/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • JE Pro Seal 100mm 0.051in Headgasket WRX/STI EJ25/EJ257 | SB1001-051
    JE Pistons

    Pro Seal 100mm 0.051in Headgasket

    Fits: WRX/STI EJ25/EJ257

    $10173
  • Up to $56 off
    In Stock
    ACT 6-puck Sprung Replacement Disc Subaru STI 2004-2020 | 6240618
    ACT

    6-puck Sprung Replacement Disc

    Fits: 04-21 WRX STI

    Only 5 left
    $23700$293.00 Save $56
    Pay over time · Est. $7.41/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $49 off
    In Stock
    ACT Performance Street Sprung Disc Subaru STI 2004-2020 | 3000503
    ACT

    Performance Street Sprung Disc

    Fits: 04-21 WRX STI

    Only 9 left
    $20900$258.00 Save $49
    Pay over time · Est. $6.53/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $48 off
    ACT 4-Puck Sprung Race Disc WRX STI 2004-2020 | 4240518
    ACT

    4-Puck Sprung Race Disc

    Fits: 04-21 WRX STI

    $20300$251.00 Save $48
    Pay over time · Est. $6.34/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $37 off
    ACT 4-Puck Rigid Race Disc WRX STI 2004-2020 | 4240018
    ACT

    4-Puck Rigid Race Disc

    Fits: 04-21 WRX STI

    $15700$194.00 Save $37
  • Up to $22 off
    In Stock
    ACT 04-21 STI Release Bearing | RB601
    ACT

    Release Bearing

    Fits: 04-21 WRX STI

    Only 10 left
    $9600$118.00 Save $22
  • Up to $194 off
    ACT 04-21 STI / 07-09 LGT Spec B Heavy Duty Sprung 4-Puck Disc Clutch Kit | SB10-HDG4
    ACT

    Heavy Duty Sprung 4-Puck Disc Clutch Kit

    Fits: 04-21 WRX STI, 07-09 Legacy GT spec.B

    $82700$1,021.00 Save $194
    Pay over time · Est. $25.84/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $204 off
    ACT Xtreme Clutch Kit 4 Puck Sprung Disc Subaru STI 2004-2020 | SB10-XTG4
    ACT

    Xtreme Clutch Kit 4 Puck Sprung Disc

    Fits: 04-21 WRX STI, 07-09 Legacy GT spec.B

    $86900$1,073.00 Save $204
    Pay over time · Est. $27.16/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $187 off
    In Stock
    ACT Heavy Duty Clutch Kit 6 Puck Solid Subaru STI 2004-21 | SB10-HDR6
    ACT

    Heavy Duty Clutch Kit 6 Puck Solid

    Fits: 04-21 WRX STI

    Only 4 left
    $79900$986.00 Save $187
    Pay over time · Est. $24.97/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $212 off
    In Stock
    ACT 04-21 STI / 07-09 LGT Spec B Xtreme Duty 6-Puck Disc Clutch Kit | SB10-XTG6
    ACT

    Xtreme Duty 6-Puck Disc Clutch Kit

    Fits: 04-21 WRX STI, 07-09 Legacy GT spec.B

    Only 3 left
    $90300$1,115.00 Save $212
    Pay over time · Est. $28.22/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $193 off
    ACT Xtreme Clutch Kit 4 Puck Solid Disc Subaru STI 2004-2020 | SB10-XTR4
    ACT

    Xtreme Clutch Kit 4 Puck Solid Disc

    Fits: 04-21 WRX STI, 07-09 Legacy GT spec.B

    $82300$1,016.00 Save $193
    Pay over time · Est. $25.72/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $197 off
    ACT Xtreme Clutch Kit 6 Puck Solid Disc Subaru STI 2004-2020 | SB10-XTR6
    ACT

    Xtreme Clutch Kit 6 Puck Solid Disc

    Fits: 04-21 WRX STI, 07-09 Legacy GT spec.B

    $84100$1,038.00 Save $197
    Pay over time · Est. $26.28/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $121 off
    In Stock
    ACT P/PL-M Heavy Duty Clutch Pressure Plate Subaru STI 2004-2020 / Legacy GT Spec B 2007-2009 | SB019
    ACT

    Heavy Duty Clutch Pressure Plate

    Fits: 04-21 WRX STI, 07-09 Legacy GT Spec B

    Only 3 left
    $51700$638.00 Save $121
    Pay over time · Est. $16.16/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $131 off
    ACT P/PL-M Xtreme Clutch Pressure Plate Subaru STI 2004-2020 / Legacy GT Spec B 2007-2009 | SB019X
    ACT

    Xtreme Clutch Pressure Plate

    Fits: 04-21 WRX STI, 07-09 Legacy GT Spec B

    $55900$690.00 Save $131
    Pay over time · Est. $17.47/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.
  • Up to $120 off
    In Stock
    ACT [04-21 STI] Prolite Flywheel | 600240
    ACT

    Prolite Flywheel

    Fits: 04-21 WRX STI

    Only 5 left
    $50900$629.00 Save $120
    Pay over time · Est. $15.91/payment
    ⓘ

    Illustrative estimate only, not a financing quote or guaranteed offer. Actual payments, frequency and terms vary by provider and eligibility. Taxes, shipping and add-ons are excluded.

The VA-chassis STI is one of the most modified platforms in the Subaru universe, and for good reason. The EJ257 responds to upgrades, the chassis rewards better suspension, and the aftermarket support is extensive. This collection brings together STI aftermarket parts for every corner of your 2015-2021 build from top brands Grimmspeed, Perrin Performance, Cobb Tuning, and more. 

  • Engine and drivetrain: intakes, turbo upgrades, exhaust systems, intercoolers, clutches and short shifters. 
  • Suspension and handling: coilovers, springs, sway bars, bushings and chassis bracing. Wheels and brakes to put it all to the ground. 
  • Let’s not forget the cosmetic upgrades: carbon fiber, lip kits, spoilers, lighting and interior accessories from JDMuscle.

Every product listing in our STI aftermarket parts collection has verified information, so you know what fits before you order.

FAQs

Do 2015 STI aftermarket parts fit all VA-generation models?

Many do: the 2015-2021 STI shares its core platform throughout. Engine, drivetrain, and suspension parts usually cross over without issue. Exterior components are the exception, since the 2018 facelift changed several body panels. Always check the fitment info on the listing.

What should I upgrade first on my STI?

Intake, cat-back exhaust, and a professional tune give you the most noticeable gains for the money and lay a foundation for everything after. If handling is your priority, coilovers or springs plus sway bars come first instead of STI aftermarket parts.

Will these parts affect my warranty?

STI aftermarket parts can affect coverage on related components, and most 2015-2021 STIs are outside factory warranty anyway. Check with your dealer if warranty status matters to your build.

Why buy STI aftermarket parts from JDMuscle?

We're a family business run by actual Subaru people. We mod our own cars and handle our own customer service. Curated brands, competitive pricing with our price match guarantee, easy returns, and same-day shipping (Saturdays included). Free shipping over $199 to the continental 48 states.