{"product_id":"acl-trimetal-reinforced-main-bearings-nissan-ka24de","title":"ACL Race Series main bearings for Nissan KA24DE","description":"\u003cp\u003eACL Race Series main bearing set for Nissan KA24DE, part number 5M2747H. These support the crankshaft in the block and, in a tuned engine, are essential for ensuring oil properly reaches the entire crankshaft.\u003c\/p\u003e\u003cp\u003eThey are trimetal bearings: SAE 1010 steel backing, a copper-lead-tin layer approximately 0.3 mm thick, a nickel barrier, and a surface overlay of lead, tin, and copper that conforms to the crankshaft surface and resists seizing.\u003c\/p\u003e\u003cp\u003eThe upper shells feature a full 180° oil groove, while the lower shells have a partial groove to avoid interrupting oil flow to the connecting rods; the end of the groove is tapered to prevent pressure spikes. Compared to stock bearings, the Race series has increased crush for better seating and heat transfer, as well as greater eccentricity to promote an oil film at high engine speeds.\u003c\/p\u003e\u003cp\u003eIn standard size, ACL specifies them for a crankshaft journal diameter of 59.962 to 59.975 mm, and recommends an oil clearance of approximately 0.061 to 0.073 mm for this diameter. If the crankshaft has been ground, the measurement changes.\u003c\/p\u003e\u003cp\u003eThey do not have the silver-tin flash plating of standard bearings, so their dark, brownish-black-bluish color is factory-standard and does not indicate any defect. ACL advises against polishing the bearing surface to adjust clearance; if more is needed, they can be combined with the HX version, which provides an additional 0.025 mm of clearance.\u003c\/p\u003e\u003cp\u003eIf the crankshaft has been ground or you are unsure of the required size, please write to us with your engine code before ordering.\u003c\/p\u003e","brand":"ACL","offers":[{"title":"Default Title","offer_id":50813143744846,"sku":"5M2747H-STD","price":119.78,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0816\/7329\/0062\/files\/16d5ec13f65313c4b7f32ebece384ec6.jpg?v=1735904145","url":"https:\/\/driftandgrip.com\/en\/products\/acl-trimetal-reinforced-main-bearings-nissan-ka24de","provider":"Drift \u0026 Grip","version":"1.0","type":"link"}