Collection: Engine Upgrades For Subaru Legacy B4 BN
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Eibach HD Adj Endlink | Subaru Forester/Outback/Legacy 11-25 (UEL-10-185HD)
Vendor:EibachRegular price $133.84 USDRegular priceUnit price / per$172.36 USDSale price $133.84 USDSale -
DeatschWerks Set of 4 2400cc Injectors for Subaru WRX 02-14/Legacy GT 07-12/STI 07-15
Vendor:DeatschWerksRegular price $989.00 USDRegular priceUnit price / per$989.00 USDSale price $989.00 USD -
COBB High Flow Fuel Pump | Subaru WRX (08-14) / STI (08-21) / Legacy GT (05-09) (315450)
Vendor:COBBRegular price $190.00 USDRegular priceUnit price / per$190.00 USDSale price $190.00 USD -
COBB One Step Colder Spark Plug Set | Subaru WRX/STI/Legacy GT/Outback XT/Forester XT (D44700)
Vendor:COBBRegular price $65.00 USDRegular priceUnit price / per$65.00 USDSale price $65.00 USD -
COBB Silicone Turbo Inlet V2 Black | Subaru WRX/Legacy GT/Outback XT (08-14/05-09) (724450)
Vendor:COBBRegular price $290.00 USDRegular priceUnit price / per$290.00 USDSale price $290.00 USD -
COBB V3 Air/Oil Separator (AOS) 1L w/ ORB Ports | Subaru WRX/STI/Legacy/Outback/Forester XT (05-21) (822615)
Vendor:COBBRegular price $595.00 USDRegular priceUnit price / per$595.00 USDSale price $595.00 USD -
COBB 4 Bar Map Sensor | Subaru WRX (08-14)/Legacy GT (05-12)/Forester XT (09-13)/Outback XT (05-09) (A22100)
Vendor:COBBRegular price $205.00 USDRegular priceUnit price / per$205.00 USDSale price $205.00 USD -
COBB MAP Sensor Adapter Kit | Subaru WRX (08-14) / Legacy GT (05-09) / Forester XT (09-13) (A22600)
Vendor:COBBRegular price $65.00 USDRegular priceUnit price / per$65.00 USDSale price $65.00 USD -
COBB 4 Bar Map Sensor Kit | Subaru WRX (08-14)/Legacy GT (05-09)/Forester XT (09-13) (A22700)
Vendor:COBBRegular price $235.00 USDRegular priceUnit price / per$235.00 USDSale price $235.00 USD -
COBB AccessPORT V3 ECU Tuner | Subaru Ascent/Outback/Legacy XT (19-22) (AP3-SUB-005)
Vendor:COBBRegular price $770.00 USDRegular priceUnit price / per$770.00 USDSale price $770.00 USD -
COBB AccessPORT V3 ECU Tuner | Subaru WRX/STI (08-14) / Legacy GT (07-12) / Forester XT (07-13) / Outback XT (07-09) (AP3-SUB-003)
Vendor:COBBRegular price $770.00 USDRegular priceUnit price / per$770.00 USDSale price $770.00 USD -
COBB LF Bypass Valve | Subaru WRX (08-14) / Legacy GT / Forester XT / Outback XT (724665)
Vendor:COBBRegular price $405.00 USDRegular priceUnit price / per$405.00 USDSale price $405.00 USD -
COBB 1050x Top Feed Fuel Injectors | Subaru WRX (02-14) / WRX STI (07-21) / Legacy GT / Forester XT (312150)
Vendor:COBBRegular price $625.00 USDRegular priceUnit price / per$625.00 USDSale price $625.00 USD -
DeatschWerks DW300 Performance Pump Module for 15-21 WRX
Vendor:DeatschWerksRegular price $424.15 USDRegular priceUnit price / per$499.00 USDSale price $424.15 USDSale -
Cometic 100mm Bore MLS Headgasket .040" | Subaru 90-01 Impreza/Legacy 2.0/2.5L (H1631SPK040S)
Vendor:Cometic GasketRegular price $47.38 USDRegular priceUnit price / per$57.59 USDSale price $47.38 USDSale -
HKS Fine Tune Upgraded Timing Belt | Subaru WRX/STI/Legacy GT/Forester XT (24999-AF001)
Vendor:HKSRegular price $286.59 USDRegular priceUnit price / per$290.00 USDSale price $286.59 USDSale -
HKS SSQV4 Blow Off Valve Kit | Subaru WRX (08-14) / Legacy 2.5 GT (05-06) (71008-AF012)
Vendor:HKSRegular price $408.94 USDRegular priceUnit price / per$434.50 USDSale price $408.94 USDSale -
DeatschWerks 05-09 Subaru Legacy GT / 08-14 WRX / 08-21 STI DW430C 430lph Compact Fuel Pump
Vendor:DeatschWerksRegular price $186.15 USDRegular priceUnit price / per$219.00 USDSale price $186.15 USDSale -
DeatschWerks 02-14 Subaru WRX / 07-14 STI/Legacy GT Bosch EV14 1200cc Injectors (Set of 4)
Vendor:DeatschWerksRegular price $569.00 USDRegular priceUnit price / per$569.00 USDSale price $569.00 USD -
aFe Pro Guard D2 Oil Filter Set of 4 | Scion FR-S / Subaru BRZ (13-17) (44-LF018-MB)
Vendor:aFeRegular price $54.00 USDRegular priceUnit price / per$54.00 USDSale price $54.00 USD
Engine Upgrades for Subaru Legacy B4 BN to Maximize Performance
Unlock the full potential of your Subaru Legacy B4 BN with engine upgrades designed specifically for this model. Our selection focuses on enhancing power, throttle response, and engine reliability through quality aftermarket parts engineered for precise fitment and lasting performance.
What Are the Key Engine Upgrades for the Subaru Legacy B4 BN?
Upgrading your Legacy B4 BN’s engine involves several core components that work together to improve performance and drivability. Performance intakes and exhaust systems increase airflow and efficiency, while cooling and forced induction parts help maintain optimal engine temperatures under load. Engine management and tuning accessories allow for precise control over fuel and ignition timing, ensuring your upgrades deliver consistent results.
- High-flow intake systems for improved air delivery
- Performance exhausts that reduce backpressure and enhance sound
- Cooling upgrades such as intercoolers and radiator enhancements
- Engine management tools including ECU tuners and sensors
- Durable engine mounts and drivetrain components for reliability
How to Choose the Right Engine Upgrades for Your Build
Selecting the right parts depends on your performance goals and daily driving needs. If you’re aiming for increased horsepower and throttle response, focus on intake and exhaust upgrades paired with proper tuning. For reliability and sustained performance, prioritize cooling solutions and reinforced drivetrain components. Always consider compatibility and fitment to avoid installation issues and ensure seamless integration with your Legacy’s engine bay.
Why Shop Engine Upgrades for Subaru Legacy B4 BN at WheelFlip?
At WheelFlip, we curate engine upgrades that meet the specific demands of the Subaru Legacy B4 BN platform. Our collection balances performance gains with fitment confidence, helping you build a reliable and powerful setup. Explore our range of intake systems, exhaust upgrades, cooling parts, and tuning accessories to enhance your Legacy’s engine performance with parts you can trust.












