{"product_id":"acl-trimetal-reinforced-main-bearings-toyota-1jz-2jz","title":"ACL Race Series main bearings for Toyota 1JZ, 2JZ","description":"\u003cp\u003eACL Race Series main bearing set for Toyota 1JZ, 2JZ, part number 7M8103H. These support the crankshaft in the block and, in a tuned engine, are essential for ensuring oil reaches the entire crankshaft properly.\u003c\/p\u003e\u003cp\u003eThese are tri-metal bearings: SAE 1010 steel backing, a copper, lead, and tin layer of approximately 0.3 mm, a nickel barrier, and a surface layer of lead, tin, and copper that conforms to the crankshaft surface and resists seizing.\u003c\/p\u003e\u003cp\u003eThe upper bearings feature a full 180° oil groove, and the lower bearings a partial groove, so as not to interrupt 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 more crush for improved seating and heat transfer, and increased eccentricity that promotes oil film formation when the engine is revving high.\u003c\/p\u003e\u003cp\u003eIn standard size, ACL specifies them for a crankshaft journal of 61.984 to 62.001 mm, and for that diameter, it recommends an oil clearance of approximately 0.063 to 0.075 mm. If the crankshaft has been ground, the dimensions change.\u003c\/p\u003e\u003cp\u003eThey do not have the silver-tin flash plating of standard bearings, so their dark, brownish-black-bluish color is the factory finish and does not indicate a defect. ACL advises against polishing the bearing surface to adjust clearance; if more is needed, they should be combined with the HX version, which provides 0.025 mm of additional 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":50813127917902,"sku":"ACL-7M8103H-STD","price":175.24,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0816\/7329\/0062\/files\/acl-main-bearings_6ae28ada-432a-4aae-a319-c64b0b878e13.jpg?v=1735903952","url":"https:\/\/driftandgrip.com\/en\/products\/acl-trimetal-reinforced-main-bearings-toyota-1jz-2jz","provider":"Drift \u0026 Grip","version":"1.0","type":"link"}