AirDog AD-BOOSTCOMP Fuel Pressure Boost Compensation Kit for II-5G / Raptor 4G

System Compatibility / Fitment

• AirDog II-5G Fuel Air Separation Systems (all engine and truck applications)
• Raptor 4G Lift Pump Systems (all engine and truck applications)

Fitment Notes

• This is a universal add-on accessory kit - it is not engine- or truck-specific. It is compatible with any vehicle running an AirDog II-5G or Raptor 4G lift pump system, including Cummins, Duramax, and Powerstroke platforms.
• This kit is NOT required for most AirDog users. It is designed for highly modified diesel trucks running elevated horsepower in a competition or demanding performance environment where standard diaphragm pressure settings are no longer sufficient under boost. Daily-driver and mildly modified AirDog users do not need this kit.
• The AirDog II-5G and Raptor 4G are the only AirDog/PureFlow systems that use an adjustable diaphragm regulator capable of accepting boost compensation input. This kit is not compatible with Original AirDog, AirDog II-4G, or Raptor 150/100 systems that use a fixed or non-diaphragm regulator.
• Installation requires running 1/4" pneumatic hardline from the engine's boost source to the boost compensation port on the AirDog or Raptor regulator. A 15-foot length of hardline is included.

Features

• Redirects compressed boost air from the engine's intake tract (post-turbo) into the AirDog or Raptor diaphragm fuel pressure regulator, triggering the regulator to increase fuel delivery pressure in direct proportion to boost. The relationship is 1:1 - each additional pound of boost pressure causes the regulator to demand one additional pound of fuel pressure from the lift pump.
• Eliminates the fuel pressure drop that occurs at wide-open throttle on high-horsepower builds, where increased injector duty cycle and elevated boost would otherwise outpace static regulator pressure settings. This keeps the injection system at full pressure across the entire RPM and load range.
• Fully adjustable air pressure regulator (0-50 psi range) allows fine-tuning of how aggressively the compensation acts across the boost curve. For mild high-HP builds the regulator can be dialed in conservatively; for maximum-effort race applications it can be set to apply maximum compensation at peak boost.
• Allows a single AirDog II-5G or Raptor 4G pump to maintain adequate fuel pressure at high-horsepower power levels without requiring a second lift pump or upgrading to a larger pump - keeping the build simpler and the fuel system more manageable.
• Works in conjunction with the AirDog and Raptor demand-flow diaphragm design, which already provides stable pressure under varying load. The boost compensation kit extends that stability into the extreme end of the load range where standard settings reach their limits.

Specifications

• Part Number: AD-BOOSTCOMP
• Brand: PureFlow AirDog
• Type: Fuel Pressure Boost Compensation Kit (add-on accessory)
• Compatible Systems: AirDog II-5G, Raptor 4G
• Adjustable Regulator Range: 0-50 psi
• Compensation Ratio: 1:1 (1 lb boost = 1 lb added fuel pressure)
• Hardline Included: 15 ft of 1/4" pneumatic hardline
• Weight: 0.2 lbs

Included Components

• 1x Mounting bracket
• 1x Adjustable air pressure regulator kit (0-50 psi)
• Fittings
• 15 ft of 1/4" pneumatic hardline
• Installation instructions

Product Description

The PureFlow AirDog AD-BOOSTCOMP is a Fuel Pressure Boost Compensation Kit designed as an add-on accessory for the AirDog II-5G and Raptor 4G lift pump systems. It is engineered for high-horsepower diesel builds where the demands placed on the fuel system under full boost and wide-open throttle exceed what a standard diaphragm regulator setting can sustain on its own.

The kit works by tapping into the engine's boost source and routing compressed post-turbo air through 1/4" pneumatic hardline into the AirDog or Raptor diaphragm fuel pressure regulator. The diaphragm regulator responds to this boost pressure signal by increasing its output pressure demand at the same rate - one pound of boost for one pound of added fuel pressure. The result is a fuel system that scales its delivery pressure in real time with engine load, rather than operating at a fixed pressure that may be adequate at light throttle but insufficient at the top of the boost curve. The adjustable regulator (0-50 psi) allows the system to be dialed in precisely for the specific boost levels and power targets of the build.

This kit is not required or necessary for the vast majority of AirDog users - it is specifically aimed at heavily modified trucks in race or extreme performance applications where every pound of fuel pressure matters at high load. For those builds, the AD-BOOSTCOMP allows a single AirDog II-5G or Raptor 4G pump to maintain full pressure across the entire operating range without stepping up to a secondary pump or a larger system. All hardware, fittings, and 15 feet of 1/4" pneumatic hardline are included.