{"product_id":"acl-trimetal-reinforced-main-bearings-mitsubishi-4g3","title":"ACL Race Series main bearings for Mitsubishi 4G3*","description":"\u003cp\u003eACL Race Series competition main bearing set (part number 5M1144H) for Mitsubishi 4G3*. These support the crankshaft in the engine block and, in a tuned engine, are responsible for ensuring proper oil delivery to the entire crankshaft.\u003c\/p\u003e\u003cp\u003eInternally, they feature three layers on a high-strength steel backing: a copper-lead-tin lining, a thin nickel barrier, and a lead-tin-copper sliding layer that works against the crankshaft.\u003c\/p\u003e\u003cp\u003eThe upper bearings have a full 180° oil groove, while the lower bearings have a partial groove to avoid restricting oil flow to the connecting rods, with a tapered groove end to prevent pressure spikes. ACL manufactures them with more \"crush\" (housing interference) than a standard bearing to ensure a secure fit and better heat dissipation, as well as increased eccentricity, which helps maintain the oil film when the housing deforms at high RPMs.\u003c\/p\u003e\u003cp\u003eIn standard size, ACL specifies this for a crankshaft journal diameter of 56.980 to 57.000 mm, and recommends an oil clearance of approximately 0.059 to 0.070 mm for that diameter. If the crankshaft has been reground, the dimensions change.\u003c\/p\u003e\u003cp\u003eThey do not have the final silver tin plating of standard bearings, so their dark color—ranging from brown and black to bluish—is the factory finish and does not indicate any defect. ACL advises against polishing the bearing surface to adjust clearance; if more is needed, combine them with the HX version, which provides an additional 0.025 mm of clearance.\u003c\/p\u003e\u003cp\u003eNot sure if your crankshaft is standard size? Write to us with your engine code and we will help you choose.\u003c\/p\u003e","brand":"ACL","offers":[{"title":"Default Title","offer_id":50813085909326,"sku":"ACL-5M1144H\/62","price":151.95,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0816\/7329\/0062\/files\/acl-main-bearings_268b5cf1-4c7b-439c-b215-b657c22719f4.jpg?v=1735903751","url":"https:\/\/driftandgrip.com\/en\/products\/acl-trimetal-reinforced-main-bearings-mitsubishi-4g3","provider":"Drift \u0026 Grip","version":"1.0","type":"link"}