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Dinan engineered this Underdrive Pulley Kit to increase power by reducing parasitic drag on the engine from spinning the alternator, water pump and AC compressor. The power increase is achieved by slowing down the speed of these accessory drives that rob power from your engine. Dinan ensures the safety of the engine by doing extensive water testing. The Dinan constructed this underdrive pulley from aircraft quality 6061 alloy and anodized black. Order today!
BMW changed the belt configuration from a single-sided power steering and AC belt to a double-sided belt for M3's that were produced after May 2008. Please check with your dealer to find the correct Dinan part number below.