Extreme Online Store

What is the best aero for a Subaru WRX or WRX STI? The best upgrades start with the front end — a CS-style front splitter and matching side skirts for your generation (15-21 or 22-26 WRX and WRX STI) transform the look, and a rear gurney flap or axle-back exhaust finishes the package. Extreme Online Store's EOS line covers exactly these parts, built as direct bolt-ons for the WRX and WRX STI chassis.

Aero parts like front splitters, side skirts, and gurney flaps manage how air moves around the car at speed, reducing lift and sharpening turn-in while giving the car a lower, wider stance. Because these are generation-specific parts — the 15-21 VA and the 22-26 VB have different bumpers and trunks — always match the part to your chassis. Most EOS aero installs with basic hand tools in a driveway.

Extreme Online Store — sold here under its EOS house label — focuses on WRX and WRX STI exterior upgrades across the 15-21 and 18-21 generations, with newer coverage for the 22-26 WRX. The catalog centers on CS-style aero: front splitter lips, front mesh grille vent covers, side skirts, and rear gurney flap spoiler extensions, all designed to work together as a matched set. Beyond aero, the EOS line also includes axle-back muffler delete exhausts with quad tips for the 22-26 WRX and window visors for the 15-21 WRX and STI, making it a one-stop option for exterior mods. Related aero from AeroFlowDynamics and OLM covers the same chassis if you want to compare designs.

Start with aero for the full category and check WRX/STI side skirts to match your splitter. Best sellers include the CS Front Splitter Lip and the Rear Gurney Flap Spoiler for 15-21 WRX and STI — plus the axle-back muffler delete for the 22-26 WRX. Read Expert Recommendations: Choosing a Front Lip for Your 2022 WRX first.

EOS Aero FAQ

Will EOS aero fit my WRX generation?

EOS parts are generation-specific — check for 15-21 WRX/STI, 18-21 WRX/STI, or 22-26 WRX in the fitment note. VA and VB bumpers differ, so confirm your chassis before ordering.

Are splitters and side skirts hard to install?

Most install with basic hand tools; splitters and side skirts mount to factory bumper and rocker points. A driveway install typically takes an afternoon — no lift required.

Does a muffler delete need a tune?

An axle-back muffler delete changes sound and appearance only — no tune required. Cat-back and downpipe changes are the ones that affect tuning.

Do you carry EOS parts beyond aero?

Yes — the EOS line also includes window visors and wind deflectors plus grille vent covers, so you can finish the whole exterior in one brand's design language.