Subaru WRX / STI Performance Parts

Maximize your Subaru's performance with our complete selection of WRX and STI upgrades. From turbo upgrades to exhaust systems, suspension, and more - we have everything you need to build your dream Subaru.

Popular WRX / STI Modifications

1. Turbo Upgrades

Factory Turbo Replacements:

• TD04 Upgrade: 300-320 HP, bolt-on replacement
• FP Green: 350-380 HP, quick spool
• FP Blue: 380-420 HP, excellent street/track balance
• Garrett G25-550: 400-500 HP, modern ball-bearing design
• EFR 7163: 450-550 HP, ultimate street turbo

Power Gains: +50-250 HP depending on turbo and supporting mods

2. J-Pipe / Downpipe Upgrades

Subaru WRX FA20 J-Pipe (2015-2021)

• Power Gains: 25-35 HP, 30-40 lb-ft torque
• Material: Stainless steel, 3" diameter
• Options: Catted or catless
• Sound: Deeper exhaust note, more turbo sounds
• Tuning: Required for best results

STI EJ257 Downpipe (2004-2021)

• Power Gains: 20-30 HP, 25-35 lb-ft torque
• Replaces: Restrictive factory up-pipe and downpipe
• Best Combined With: Catless up-pipe for maximum gains

3. Exhaust Systems

Cat-Back Exhaust:

• Invidia N1, Q300, R400
• Borla S-Type, ATAK
• Cobb Tuning
• Power Gains: 5-15 HP (more with J-pipe)
• Sound: Aggressive Subaru rumble

4. Suspension Upgrades

Coilovers:

• BC Racing BR Series: $1,000-$1,400
• Fortune Auto 500 Series: $1,200-$1,600
• KW V3: $2,500-$3,000
• Ohlins Road & Track: $2,800-$3,500

Sway Bars:

• Whiteline adjustable sway bars
• Reduce body roll
• Improve cornering
• Better turn-in response

5. Intake Systems

Cold Air Intakes:

• Cobb SF Intake: $350-$450
• AEM Cold Air Intake: $300-$400
• Grimmspeed: $400-$500
• Power Gains: 5-10 HP, better turbo sounds

WRX / STI by Generation

GD/GG WRX / STI (2002-2007)

• Engine: EJ205 (WRX), EJ257 (STI)
• Power: 227-300 HP
• Popular Mods: VF39 turbo, STI top-mount intercooler, up-pipe, downpipe
• Known Issues: Ringland failure (EJ257), head gaskets

GR/GV WRX / STI (2008-2014)

• Engine: EJ255 (WRX), EJ257 (STI)
• Power: 265-305 HP
• Popular Mods: Cobb Accessport, J-pipe, intake, turbo upgrade
• Known Issues: Ringland failure, turbo failure (WRX)

VA WRX (2015-2021)

• Engine: FA20DIT (2.0L turbo)
• Power: 268-310 HP
• Popular Mods: J-pipe, intake, Accessport, turbo upgrade
• Advantages: Direct injection, more reliable than EJ

VA STI (2015-2021)

• Engine: EJ257 (2.5L turbo)
• Power: 305-310 HP
• Popular Mods: Same as previous STI generations
• Note: Last generation with EJ257

VB WRX (2022-2024)

• Engine: FA24DIT (2.4L turbo)
• Power: 271-275 HP
• Popular Mods: J-pipe, intake, Accessport (new platform, growing aftermarket)
• Advantages: Larger displacement, more torque

Bolt-On Build Guide

Stage 1 (Tune Only) - $650

• Cobb Accessport: $650
• Power Gains: +30-40 HP, +40-50 lb-ft
• Best bang-for-buck mod!

Stage 2 (Bolt-Ons) - $2,000-$3,000

• Cobb Accessport: $650
• J-Pipe/Downpipe: $400-$800
• Cold Air Intake: $350-$450
• Cat-Back Exhaust: $800-$1,500
• Power Gains: +60-80 HP, +70-90 lb-ft

Stage 3 (Turbo Upgrade) - $5,000-$8,000

• All Stage 2 mods
• Turbo Upgrade: $2,000-$4,000
• Fuel System: $800-$1,500
• Pro Tune: $600-$1,000
• Power Gains: +100-200 HP (total 370-500 HP)

Common WRX / STI Issues & Solutions

Ringland Failure (EJ257)

Problem: Piston ringland cracks, usually cylinder #4

Cause: Detonation, poor tuning, aggressive driving

Solution: Proper tuning, quality fuel, built engine for high boost

Head Gasket Failure (EJ Engines)

Problem: External coolant leaks around 100k miles

Cause: Factory multi-layer steel gaskets

Solution: Replace with OEM or upgraded gaskets

Turbo Failure (WRX)

Problem: Factory turbo fails around 100k miles

Cause: Wear and tear, oil starvation

Solution: Replace with upgraded turbo, regular oil changes

WRX / STI Tuning

Cobb Accessport

• Price: $650-$750
• Features: Pre-loaded maps, data logging, gauge display
• Best For: Stage 1 and Stage 2 builds
• Power Gains: +30-80 HP depending on mods

E-Tune (Remote Tuning)

• Price: $400-$600
• Process: Data logging, email revisions
• Best For: Stage 2+ builds
• Tuners: Brentuning, Torqued Performance, Phatbotti

Dyno Tune (Custom)

• Price: $600-$1,200
• Process: In-person dyno tuning
• Best For: Stage 3+, built engines, E85
• Results: Maximum power, best reliability

Track Day Essentials

Must-Have Upgrades:

• Performance brake pads (Hawk, EBC)
• Stainless steel brake lines
• High-temp brake fluid (Motul RBF600)
• Oil cooler (prevents oil temps from spiking)
• Upgraded radiator
• Performance tires (Michelin PS4S, RE-71RS)

Subaru Community

Join the Community:

• NASIOC Forums (North American Subaru Impreza Owners Club)
• r/WRX and r/SubaruWRX on Reddit
• Local Subaru meets and cruises