for Subaru WRX/STi (all years) Boost Cooler Kit
• Stage-2
  
  
  For Subaru WRX's utilizing the stock 0-5 volt output MAF sensor. Also works on STi'. The Digital Variable Control unit proportionally injects more or less water-ethanol according to input signals from the mass air flow sensor. More power over a wider range and better drivability is the result 20-percent increases in Horsepower typical.

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

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