{"product_id":"turner-motorsport-e70-x5-35d-clutched-alternator-pulley-conversion-kit","title":"Turner Motorsport E70 X5 35d Clutched Alternator Pulley Conversion Kit","description":"\u003cdiv class=\"productlongdesc\"\u003e\n\u003cp\u003eIf you own an M57-equipped BMW, you already know this twin-turbo diesel powerplant is an absolute torque monster. What you might also know is that all that low-end grunt and high-compression diesel vibration wreaks absolute havoc on your accessory drive system.\u003c\/p\u003e\n\u003cp\u003eFrom the factory, both the E90 335d and E70 X5 35d utilize a rigid alternator pulley. With each cylinder's fire, the crankshaft experiences a violent micro-acceleration. Because the alternator has a heavy internal rotor spinning at high speeds, it wants to keep spinning at a constant rate. When the engine suddenly slows down (even minutely between firing cycles), the alternator fights the belt. This constant tug-of-war results in extreme stress on your engine's belt-driven components. At best, it’s an annoying, unrefined chirp at idle; at worst, it’s a ticking time bomb for your expensive harmonic balancer.\u003c\/p\u003e\n\u003cp\u003eTo solve this issue, many enthusiasts choose to run a clutched alternator pulley (also called an overrunning alternator pulley). A clutched pulley allows the alternator to \"freewheel\" or coast when the engine slows down, completely isolating its rotational inertia from the belt drive to prevent component wear. While the N52's clutched pulley (12317560483) is a straight bolt-on, the offset is incorrect for the E70 35d's accessory drive. This simple, zinc-coated spacer from Turner Motorsport provides the precise amount of spacing needed to perfectly align the new pulley with existing belt drive components. \u003c\/p\u003e\n\u003cp\u003eFEATURES\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eAlloy steel construction provides long-lasting durability\u003c\/li\u003e\n\u003cli\u003eZinc-coated for optimal corrosion resistance\u003c\/li\u003e\n\u003cli\u003ePrecision-crafted for compatibility with the OEM alternator (12317799204) and N52 clutched alternator pulley (12317560483)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eKIT CONTENTS\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eOE N52 Clutched Alternator Pulley (12317560483)\u003c\/li\u003e\n\u003cli\u003eTurner Motorsport Clutched Alternator Pulley Conversion Spacer\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Turner Motorsports","offers":[{"title":"Default Title","offer_id":67790157545776,"sku":"5482508","price":102.95,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/7582\/4176\/files\/2094618_x800_aa019a3b-76e5-400a-88c9-cc7a9e5e5db9.jpg?v=1789509242","url":"https:\/\/es-performance.com\/fr\/products\/turner-motorsport-e70-x5-35d-clutched-alternator-pulley-conversion-kit","provider":"Eurosport Performance","version":"1.0","type":"link"}