Mods & Parts

From bolt-ons to full builds — honest reviews of parts and mods for Subaru enthusiasts. We test fitment, compare alternatives, and tell you what's actually worth the money.

Exhaust

Best Exhaust Systems for WRX & STI

On a stock-tuned VA/VB WRX, a catback alone nets 2–4 whp and a meaner burble. The real gains start with an EL header + catted downpipe + Stage 2 tune (~50 whp on E85).

Invidia N1 catback

$680

Loudest of the budget catbacks. Drone at 2,500 rpm on the highway is real — bring earplugs for long trips.

COBB SS 3-inch catback

$1,099

Quieter, no drone, fits like OEM. The pick if your daily commute is >30 min.

GrimmSpeed catted downpipe

$849

Catalyst keeps CEL away on most ECUs. Required before any Stage 2 tune.

Fitment

2015–2021 VA WRX/STI · 2022+ VB WRX (3-inch only) · Add a tune — straight pipe + stock map will trigger fueling DTCs.

Parts on Amazon

Shop exhaust parts on Amazon

Curated by SubaruReview · prices vary

Paid link · we earn a small commission

Suspension

Subaru Lowering Springs — Drop, Ride & Picks

A 1–1.5" drop on stock struts is fine for daily use. Anything past that and you're killing your KYBs in under a year — go coilovers instead.

Eibach Pro-Kit

$310

1.2" front / 1.0" rear. Best ride quality of any spring. The safe daily-driver pick.

RCE Tarmac 2

$425

Made for Subarus. 0.75" drop, stiffer rates, pairs with stock or aftermarket struts.

BC Racing BR coilovers

$1,195

If you want adjustable height + 30-way damping for $1,200, this is the entry point.

Fitment

Springs are model/year specific — VA WRX springs don't fit VB. Always replace top hats + bump stops at install (Whiteline KCA414).

Parts on Amazon

Shop suspension parts on Amazon

Curated by SubaruReview · prices vary

Paid link · we earn a small commission

Exhaust

Legacy GT (2005–2009) Exhaust Guide

EJ255 Legacy GT exhausts are getting rare — most aftermarket support dried up around 2015. Stick to used Cobb or Invidia, or have a 3-inch custom built.

Used Invidia Q300 (BL/BP)

~$400 used

$400 used on Legacy GT Forums. Bolt-on, OEM-style hangers, sounds great with a TBE.

COBB SS turboback (discontinued)

$900–1,200 used

Holy grail. Includes downpipe + uppipe. Listings appear monthly on legacygt.com classifieds.

Custom 3" mandrel-bent

$650 custom

$650 at a competent muffler shop. Bring an OEM-pattern Magnaflow 14416 muffler and Vibrant resonator.

Fitment

BL/BP chassis only · EJ255 turbo · 5MT and 5EAT both work. Don't reuse the OEM uppipe — it cracks at 100k.

Parts on Amazon

Shop exhaust parts on Amazon

Curated by SubaruReview · prices vary

Paid link · we earn a small commission

Getting Started

Essential First Mods for Any WRX

Skip the wing, skip the wrap. The mods that actually matter are the ones that protect the engine, fix factory pain points, and unlock tuning. Do these four before anything cosmetic.

COBB AccessPort V3

$675

The single most important purchase. Off-the-shelf Stage 1 = 25 whp on 93 oct, no other parts needed.

Killer-B oil pickup + baffled pan

$550

EJ25 oil starvation in left-handers is real. $550 prevents a $7,000 short block.

Perrin master cylinder brace

$129

Fixes mushy pedal feel on VA/VB. 10-minute install with a 10mm socket.

Whiteline rear sway bar

$285

Kills understeer instantly. Run on softest setting first, work up to firm.

Fitment

Universal across VA (2015–2021) and VB (2022+) WRX · AP V3 also supports 2008+ STI · Killer-B pickup is EJ25-specific.

Parts on Amazon

Shop getting started parts on Amazon

Curated by SubaruReview · prices vary

Paid link · we earn a small commission

How we review parts

Every part on this site is tested on a member's car — either the editor's daily VA WRX or a community member's build. We don't accept payment for placement, and affiliate links never change rank order.

Bench install times

Stock-vs-modded dyno

12-month durability check-in

OEM hardware compatibility

Decibel readings (in-cabin & outside)

Drone frequencies (RPM + Hz)

Failure modes from forum data

Resale value impact

→ Read our full review methodology

Mods & Parts

Best Exhaust Systems for WRX & STI

Invidia N1 catback

COBB SS 3-inch catback

GrimmSpeed catted downpipe

Subaru Lowering Springs — Drop, Ride & Picks

Eibach Pro-Kit

RCE Tarmac 2

BC Racing BR coilovers

Legacy GT (2005–2009) Exhaust Guide

Used Invidia Q300 (BL/BP)

COBB SS turboback (discontinued)

Custom 3" mandrel-bent

Essential First Mods for Any WRX

COBB AccessPort V3

Killer-B oil pickup + baffled pan

Perrin master cylinder brace

Whiteline rear sway bar

How we review parts

Ready to buy or refresh your current build?