Cobb 08-21 Subaru STi Fuel Pressure Regulator Kit

COBB Tuning Performance Parts deliver proven power gains with factory-like drivability backed by an "Engineered Performance" approach trusted by enthusiasts, pro tuners, and performance shops worldwide. Founded in 1999 and now headquartered in Austin, Texas, COBB designs, engineers, tests, and supports its products in-house to ensure reliable results across today's most popular performance platforms. Shop the full lineup of COBB Tuning performance parts at Black Ops Auto Works, including ECU tuning solutions, bolt-on upgrades, and staged power packages built to work together for predictable, repeatable performance. COBB ECU Tuning & Accessport The COBB Accessport is one of the most trusted ECU tuning devices in the industry. It enables safe ECU flashing, live data monitoring, diagnostics (read/clear codes), and tuning management helping drivers unlock stronger throttle response, improved drivability, and dependable horsepower and torque gains when paired with the right supportin...

This engine parts collection covers oil catch cans, thermostats, thermostat housings, radiator components, coolant accessories, engine covers, fuse box covers, cap covers, throttle bodies, supercharger pulleys, idler pulleys, tensioner pulleys, and engine bay dress-up parts for trucks, SUVs, muscle cars, boosted builds, high-horsepower street cars, and performance vehicles that need better reliability, cooling, airflow, oil control, and under-hood styling. The collection is particularly strong for Dodge Challenger, Charger, Durango, Jeep Grand Cherokee Trackhawk, and Ram TRX platforms running 6.2L Hellcat, 6.4L HEMI, and 5.7L HEMI engines, where oil catch can and cooling upgrades address known OEM weaknesses in the PCV and thermal management systems. Import performance platforms including GM LS-based builds, Chevrolet Camaro, and Corvette applications are also represented through Mishimoto, CSF, and ZPE GripTec product lines. Builders who invest in engine bay organization and reliab...

A properly designed fuel delivery system is the backbone of any high-performance engine build, ensuring the injectors or carburetor receive a consistent supply of fuel at the correct pressure regardless of engine load, RPM, or fuel demand. From factory replacement pumps keeping daily drivers on the road to high-flow in-tank modules supporting 1000-horsepower builds, the right fuel delivery components prevent lean conditions, injector damage, and fuel starvation at the worst possible moment. Modern EFI systems are particularly sensitive to fuel pressure variation, with even small drops causing misfires and power loss under hard acceleration. Whether you are restoring a factory system or engineering a purpose-built race setup, matching pump flow rate and fuel pressure regulation to your injector and engine requirements is essential. Popular Upgrades Top-selling fuel delivery components include Aeromotive Phantom in-tank fuel pump kits that retrofit into factory tanks without custom fa...

A fuel pressure regulator maintains consistent rail or bowl pressure regardless of engine demand, fuel pump output variation, or manifold vacuum changes, acting as the pressure control valve that determines how much fuel the injectors or carburetor actually sees at any given moment. In return-style EFI systems, the regulator bleeds excess fuel back to the tank while holding the supply side at a precise setpoint, typically 43.5 PSI for most port EFI applications. In boost-referenced setups, the regulator increases fuel pressure proportionally with boost pressure to maintain a constant fuel-to-air pressure differential as manifold pressure rises, preventing the injector effective flow rate from dropping under boost. Selecting the correct regulator type, pressure range, and port sizing for your system determines how accurately fuel delivery tracks engine demand across the full operating envelope. Popular Upgrades Top-selling fuel pressure regulators include the Aeromotive 13129 adjusta...