ACL Bearings Engine Bearing Kit

ACL Engine Bearing Kits: Precision Engineering for Every Build

When it comes to engine bearing kits, few names carry as much weight in the engine-building world as ACL Bearings. ACL Race Series performance bearings are products of more than a half-century of bearing design, engineering, metallurgy, and manufacturing experience, and that depth of expertise is on full display in every engine bearing kit they produce. ACL has one of the largest ranges of automotive engine bearings in the world, with kits spanning everyday street rebuilds all the way to championship-winning race engines.

Three Distinct Product Lines to Match Your Build

ACL structures its engine bearing kit lineup around three core metallurgies, giving engine builders a clear path from OEM replacement to all-out competition.

• Race Series (Trimetal / Duraglide): Track-proven to provide optimum performance, endurance, and durability essential for higher RPM engines. The unique combination of design, metallurgy, and engineering provides Race Series performance bearings with the endurance and capability to perform where others cannot. These kits use a copper-lead-tin lining over a high-tensile SAE1010 steel back, with a lead-tin-copper overlay for seizure resistance.
• Aluglide: Aluglide rod and main bearings were developed for OEM engines and have inherent physical properties perfectly suited for replacement applications, with a proprietary composition comprised of aluminum, tin, and silicon. Aluglide bearings are highly preferred in modern import engines that have been designed for aluminum-based bearings as OE standard fitment.
• Duraglide F780: Plain and flanged bearings are manufactured in this heavy-duty, tri-metal copper-lead material to suit every performance requirement. These kits excel in demanding rebuild scenarios where high load capacity and fatigue resistance are priorities.

What Sets ACL Race Series Bearing Kits Apart

Within the Race Series kits, ACL incorporates several engineering details that distinguish them from standard replacement sets. Hardened steel backs on all rod bearings improve the support of the bearing lining and assist with bearing retention in the housing. Increased eccentricity compensates for bore distortion at high RPM and assists in the formation of hydrodynamic oil films. Three-quarter grooved main bearings optimize bearing load-carrying surface area and oil flow to the connecting rod bearings. Tight, consistent wall tolerances help engine builders maintain consistent clearances — a detail that matters enormously when blueprinting an engine for maximum reliability.

ACL also offers application-specific kit variations. The HX suffix denotes Race Series kits with 0.025 mm (0.001") extra clearance, while the HD suffix indicates kits with location dowel holes for conrods equipped with dowel-pin bearing retention. Some Race Series sets include two thrust bearings — upper and lower — to accommodate heavier thrust loads from high-performance clutch setups.

Trusted from the Street to the Strip

Race Series rod and main bearings are standard components in race engines that have set records and won championships from Mexico to Bonneville — from sport compact drift racing to small block NASCAR, IHRA, and NHRA competitions. Yet ACL Race bearings work equally well in street machines that are rarely used at maximum power but are expected to have a normal engine life. ACL's experience includes designing and manufacturing bearings for GM, Ford, Toyota, and Mitsubishi, giving their kits an OEM-grade foundation that aftermarket builders then push even further.

With 126 engine bearing kit SKUs available, ACL covers a broad range of 4, 6, and 8-cylinder domestic and import applications. Whether you're doing a factory-spec rebuild or building a boosted street car, ACL's engine bearing kits offer the right combination of material science and engineering precision for the job.