Application: 2004-2011 Subaru Impreza WRX STi

The COBB XLE BPV is a compact and lightweight by-pass valve is capable of holding very high boost pressure without leaking and its unique design allows extremely fast venting of boost when actuated. It is designed to operate in multiple venting modes and can be quickly reconfigured using simple hand tools. Innovative engineering and precision manufacturing result in a compact package able to fit in the confines of a tight engine bay.

FEATURES

Body

• Body, mounting flange and secondary outlet cover are constructed of 6061 T6 aluminum.
• The body is hard anodized for additional strength.
• The primary outlet is rectangular in shape to provide maximum cross sectional area for venting pressurized air as quickly as possible.
• The secondary outlet cover can be removed to enable partial vent to atmosphere or full vent to atmosphere modes.
• Unit height is only 3.5 inches from base of flange to top preload adjuster,allowing it to fit into the tightest of locations.
• Body to mounting flange interface is o-ring sealed, allowing flanges of different shapes to work on multiple applications.
  
  

Piston

• Lightweight aluminum piston allows faster reaction time than heavier pistons.
• The aluminum piston has been hard anodized and impregnated with Teflon to provide smooth movement, reduce surface wear and minimize maintenance.
• Rounded piston profile smooths air flow as it passes through they cylinder.
• The rounded piston profile mates with a rounded piston seat for superior sealing when the BPV is closed.
• Tight tolerance o-rings are used to seal piston to cylinder bore properly at normal engine operating temperatures without sacrificing piston speed.

Preload Adjuster and Spring

• Adjuster allows adjustment of spring preload for fine tuning release pressure.
• Spring and spring seat are constructed of 303 stainless steel.
• Spring preload adjustment mechanism and fasteners are stainless steel.

Operation

• Valve vents pressurized air very quickly due to lightweight components, port shape and low sliding friction.
• Unique exhaust sound due to speed of air release.
• Construction materials make the XLE BPV compatible with alcohol/water injection due to inherent corrosion resistance.
• Lighter than most aftermarket BPVs and BOVs.
  

OPERATING MODES

Full Recirculation - Outlet is plumbed back into the intake tract pre-turbo. This configuration provides the best driveability with stock based MAF systems. This configuration generates the least amount of noise.

Hybrid Mode - Outlet is plumbed back into the intake tract pre-turbo and the auxiliary port cover is removed. When the piston is more than 30% open, the auxilliary port is opens, audibly venting to atmosphere. Less than 30% open results in full recirculation to improve driveability.

Full Atmosphere - Outlet and auxiliary port are open to atmosphere. Recommended only for MAP based air metering. This configuration generates the highest sound levels.

ADJUSTMENT

Spring Preload - Spring preload determines the pressure differential across the BPV piston required before the BPV opens and releases the pressurized intake charge. The COBB XLE BPV can be adjusted by loosening the locknut and turning the allen-head shaft clockwise for more preload or counter-clockwise for less preload. Once preload is set, the locknut is retightened and ensures the adjustment is secure.

MOTORSPORTS

Race proven technology for your Mazda. The 800 all wheel horsepower COBB Tuning Motorsports Time Attack R35 GT-R has utilized the COBB XLE BPV to dominate the 2010 Redline Time Attack AWD Modified class as well as smash several track records across the United States. This rigorous testing environment has proven XLE BPV's elegant design and attention to detail are only surpassed by its dependability and superior performance.