ASP Aluminum Underdrive Pulley Kit
- Increase Horsepower
- Added Detail
- Satin or "Clear" Finish Pulleys
- Billet Aluminum Construction
- 25% Underdrive Crank
- 15% underdrive Water Pump
- 950 RPM Full Charge
- Installs with simple hand tools
What's in the Box
- (1) 25% Crank Pulley
- (1) 15% Water Pump Pulley
- (1) 2.47" Alternator Pulley
Underdrive pulley systems increase engine horsepower by reducing the amount of power required to drive external engine accessories. For example, the alternator, power steering, water pump and air compressor rob horsepower from the engine. By replacing factory-sized crank and accessory drive pulleys with a resized pulley, the accessories are slowed, resulting in more horsepower available to the drive wheels. Typically, a set of Auto Specialties street pulleys will increase horsepower by 12-15, and increase mileage by 2 to 3 MPG. All pulleys are manufactured from Billet Steel or Aluminum, exceeding factory quality.
Due to the difference in diameter from the stock Mustang pullies, the alternator and charging system may need to be upgraded if you have a large stereo system.
Fits 1979-1993 V8 Mustangs
- Alternator Pulley - 2.47"
- Crank Pulley - 4.625"
- Water Pump Pulley - 5.438"
The alternator pulley in this kit will only work with the stock 75 amp alternator. The underdrive alternator pulley will NOT work on 3g upgrades.
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