SPL Parts

What are the best SPL Parts upgrades for a WRX, STI, or BRZ? The adjustable rear lower control arms and toe arms are the top picks — they unlock real camber and toe adjustment that the factory arms don't offer. For 2015-2021 STI and 2013-2021 BRZ owners dialing in an alignment for track or aggressive street use, SPL's arm and link kits are purpose-built for the job.

SPL Parts makes fully adjustable suspension hardware for Subaru's sport platforms. The catalog centers on five jobs: rear lower control arms for camber adjustment, rear toe arms for toe adjustment, front end links that connect the sway bar solidly, bumpsteer correction kits that fix tie-rod geometry on lowered cars, and eccentric lockout kits that replace the factory cam bolts with a fixed, repeatable adjustment. Fitments are chassis-specific — the rear lower control arms cover the 2015-2026 WRX, 2015-2021 STI, and 2013-2026 BRZ/86, while the front bumpsteer kit fits the 2008-2021 WRX/STI and 2013-2021 BRZ.

SPL Parts: alignment parts for drivers who measure

SPL Parts designs around one idea: an alignment you can set precisely and that stays set. The rear lower control arms and toe arms replace the factory stamped arms with rigid, adjustable links, so camber and toe can be dialed in degrees rather than fought through factory slots. On cars running the 2015+ WRX/STI or BRZ/86 rear suspension, that means you can actually hit track camber numbers and hold them through hard driving.

The supporting pieces solve the geometry problems that come with lowering. The front bumpsteer correction kit (TRE-FRS) repositions the tie rods on the 2008-2021 WRX/STI and 2013-2021 BRZ to restore proper steering geometry, while the eccentric lockout kit deletes the factory eccentric cam bolts — a known source of alignment slip — in favor of a fixed adjustment that won't move under load. Up front, the PRO front end links for the 2013-2016 Scion FR-S, 2013+ BRZ, and 2017+ 86 give the sway bar a solid, adjustable connection instead of the flexible stock link.

Shop the collection

Browse all SPL Parts, then explore the related suspension categories: suspension, control arms, and suspension bushings. Start with the rear lower control arms and the rear toe arm, add the eccentric lockout kit to lock the alignment in, and read how aftermarket parts can improve your vehicle's handling.

Frequently asked questions

Do SPL Parts arms require an alignment after install?

Yes — always get a professional alignment after installing control arms, toe arms, or end links. The whole point of adjustable arms is to set camber and toe precisely, which only an alignment rack can do.

Do I need a tune for SPL suspension parts?

No. Suspension arms and links are mechanical — no ECU changes required.

What does the eccentric lockout kit do?

It replaces the factory eccentric cam bolts with a fixed adjustment. Factory eccentrics can slip under hard driving; the lockout keeps your alignment where you set it.

Will the rear lower control arms fit my 2022+ WRX?

The arms in this collection list 2015-2026 WRX fitment, which includes the 2022+ chassis. Always confirm your exact year and model on the product page.