3-Piece Underdrive Pulley Kit

The SR Performance Underdrive Pulleys are a 3-piece kit designed to reduce parasitic drivetrain loss, freeing up an estimated 10-15 horsepower without compromising essential cooling and charging functions. These pulleys are CNC-machined from lightweight, aircraft-grade aluminum alloy for superior strength and durability. The black powder-coated finish not only provides an aggressive aesthetic but also ensures long-lasting corrosion resistance. Installation is designed to be straightforward, typically completed in under 2 hours with no modifications required. This kit reuses the factory belt. It is specifically engineered for late 2001 to 2004 GT Mustangs equipped with the SOHC 4.6L V8 engine and a short water pump (identified by a bowed-in face). A technical note highlights a design change in the 4.6L engine's water pump for the 2001 model year. Earlier pumps (1996 to mid-2001) had a longer shaft, while newer pumps (January 2001 onwards) feature a shorter shaft, necessitating a specific pulley design. This SR Performance kit is confirmed to fit GT Mustangs with the short water pump and a bowed-in pulley face.