{"product_id":"acl-trimetal-reinforced-rod-bearings-nissan-vk45-vk50-vk56","title":"ACL Race Series connecting rod bearings for Nissan VK45, VK50, VK56","description":"\u003cp\u003eACL Race Series connecting rod bearing set for Nissan VK45, VK50, VK56, part number 8B2990H. This is ACL's competition range, the same as those used in drift, circuit, and drag racing engines.\u003c\/p\u003e\u003cp\u003eThese are tri-metal bearings: SAE 1010 steel backing, a copper-lead-tin layer about 0.3 mm thick, a nickel barrier, and an overlay of lead, tin, and copper that conforms to the crankshaft surface and resists seizure. In the connecting rod bearings, the overlay is thinner to better withstand fatigue.\u003c\/p\u003e\u003cp\u003eCompared to a standard bearing, the Race range has more crush in the housing, which improves retention and heat transfer, as well as greater eccentricity that promotes an oil film when the engine is running at high RPM.\u003c\/p\u003e\u003cp\u003eIn the standard size, ACL specifies this for a connecting rod journal of 53.962 to 53.974 mm, with a bearing width of 18.3 mm. For that diameter, they recommend an oil clearance of about 0.056 to 0.067 mm, measured with a micrometer and bore gauge. If the crankshaft has been reground, the measurement changes.\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\u003eBefore ordering, confirm your crankshaft measurement (standard or reground); if you have any questions, write to us with your engine code.\u003c\/p\u003e","brand":"ACL","offers":[{"title":"Default Title","offer_id":50813097607502,"sku":"ACL-8B2990H\/92","price":244.01,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0816\/7329\/0062\/files\/acl-rod-bearings_6edc4f47-d50a-4c87-a60a-31570f0b1876.jpg?v=1735903824","url":"https:\/\/driftandgrip.com\/en\/products\/acl-trimetal-reinforced-rod-bearings-nissan-vk45-vk50-vk56","provider":"Drift \u0026 Grip","version":"1.0","type":"link"}