Get back the power and torque your belt-driven accessories steal with this underdrive pulley kit. Bolt on 8-10 “free” horsepower with Steeda’s underdrive pulleys. These pulleys slow down your accessories about 25%, reducing the drag on your engine and even slightly bumping up gas mileage. The pulleys are manufactured from billet steel, exceeding factory quality. They're also SFI race approved. The one-piece crankshaft pulley uses a injection-molded bonded-rubber damper, making it far more durable than "piggyback style" underdrive pulleys. Important Note for 2001 Mustang Midway through the production run for the 2001 model year Ford changed the design of the water pump on the 4.6L engine. The older style pump produced from 1996 to mid 2001 had a longer shaft. In January of 2001 the design of the pump was changed to a shorter shaft. This necessitated a change in the design of the pump pulley. Click the link at the bottom of the page to determine if you need the “early” or “Mid/Late” style kit. Note: Mach 1 doesn’t use the alternator pulley included in the kit. Fits 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 GT 701-0002$249.95 Year & Model: 96 to Early 01 GT96-99 Cobra & 01 BullittMid 01-04 GT & Mach 12001 Cobra 2001 Water Pump Identification GuideClick link for info PumpGuide www.realspeedauto.com Ph.631-563-7325 All parts listed are for the Ford Mustang unless otherwise noted. Copyright 2018 Realspeed Automotive Inc. All rights reserved.