{"product_id":"acl-trimetal-reinforced-main-bearings-toyota-4a-ge-4a-gze","title":"ACL Race Series main bearings for Toyota 4A-GE, 4A-GZE","description":"\u003cp\u003eACL Race Series main bearing set for Toyota 4A-GE, 4A-GZE, part number 5M1695H. These support the crankshaft in the block, and in a tuned engine, they are responsible for ensuring oil reaches the entire crankshaft properly.\u003c\/p\u003e\u003cp\u003eThe structure is trimetal, featuring a steel back, a copper-lead-tin lining, a nickel barrier, and a soft surface layer that adapts and prevents seizing, even under very high loads.\u003c\/p\u003e\u003cp\u003eThe upper shells have a full 180° oil groove, while the lower shells have a partial groove to avoid restricting oil flow to the connecting rods, with a progressive groove end to prevent pressure spikes. ACL manufactures them with more \"crush\" (housing interference) than standard bearings to ensure a secure fit and better heat dissipation, as well as increased eccentricity to help maintain the oil film when the housing deforms at high RPM.\u003c\/p\u003e\u003cp\u003eIn standard size, ACL specifies this for a crankshaft journal of 47.985 to 48.000 mm, and recommends an oil clearance of approximately 0.051 to 0.061 mm for that diameter. If the crankshaft has been reground, the measurement changes.\u003c\/p\u003e\u003cp\u003eThey do not have the silver tin flash plating of standard bearings, so their dark color—ranging from brown to black and blue—is factory-standard and does not indicate any defect. ACL advises against polishing the bearing surface to adjust clearance; if more clearance is needed, they should be combined 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":50813123199310,"sku":"ACL-5M1695H","price":86.5,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0816\/7329\/0062\/files\/acl-main-bearings_50956669-1e0f-479c-af50-56c7a1cc1928.jpg?v=1735903925","url":"https:\/\/driftandgrip.com\/en\/products\/acl-trimetal-reinforced-main-bearings-toyota-4a-ge-4a-gze","provider":"Drift \u0026 Grip","version":"1.0","type":"link"}