ACL Honda F20C/F22C Bearing Set – BC4060: The Definitive OEM+ Solution for S2000 Performance & Longevity

In the stratified world of high-performance engine building, where every component is a calculated variable in the equation of power and reliability, the bearing set is the unsung linchpin. It is the critical interface between the rotating assembly and the stationary engine block, a component that tolerates no compromise. For Honda’s legendary F20C and F22C powerplants—engines renowned for their stratospheric redlines, precise engineering, and relentless demand on internal components—the selection of bearings is not a maintenance item; it is a foundational performance decision. The BC4060 ACL Race Series Main Bearing Set embodies this philosophy. This is not a generic replacement; it is an OEM+ engineered system designed for the mechanic, builder, and enthusiast who understands that true performance is built from the crankshaft up. Utilizing ACL’s race-proven tri-metal technology while maintaining strict OEM sizing, this bearing set provides the optimal balance of fatigue strength, conformability, and embedded-ability required to support elevated horsepower, aggressive RPM excursions, and sustained track abuse, transforming a critical wear item into a cornerstone of durability.

Engineering Philosophy: Beyond Replacement, A Performance Upgrade

The common misconception is that a bearing is a simple sleeve of metal. In reality, it is a complex, multi-layered tribological component tasked with managing extreme loads, dissipating heat, and protecting both the crankshaft journal and the block itself. The ACL Race Series bearings, as supplied in the BC4060 kit for Honda F20C/F22C applications, are built on a tri-metal (or trimetal) substrate. This construction is the industry standard for serious performance and racing applications because each layer serves a distinct, critical function. The backing layer is a high-strength steel shell, providing the necessary structural rigidity to prevent distortion under load. Bonded to this is a central layer of a copper-lead alloy, chosen for its exceptional embedability—the ability to absorb minute particles of debris that would otherwise score the crankshaft—and its superior load-dispersing characteristics. The final facing layer is an electroplated aluminum-tin-silicon (AlSnSi) overlay. This soft, corrosion-resistant surface provides outstanding conformability, allowing the bearing to subtly adapt to microscopic imperfections in journal geometry or alignment, ensuring a consistent oil film across the entire bearing surface.

Why OEM Sizing is the Smart Choice for Performance Builds

A critical specification of the BC4060 set is its adherence to OEM standard sizing. In an era where “oversized” or “undersized” bearings are often mistakenly viewed as a performance necessity, ACL’s approach is refreshingly pragmatic. For the vast majority of builds—including those using a standard stroke crankshaft that has been properly polished or reground to the correct specification—OEM sizing is optimal. It ensures the designed oil clearance is achieved without the guesswork or potential for error introduced by non-standard sizes. The precision of ACL’s manufacturing guarantees that these bearings will deliver the consistent clearance mandated by Honda’s engineers, which is crucial for maintaining optimal oil pressure, especially in a high-RPM engine like the F20C/F22C where hydrodynamic lubrication is paramount. This allows the builder to focus on precision assembly, confident that the bearing dimensions are a known, reliable constant.

Technical Advantages & Direct Benefits

The BC4060 bearing set translates its advanced material science into tangible, measurable benefits for your Honda powerplant. The advantages are most apparent under the extreme conditions for which these engines are often used.

• Superior Fatigue Strength & Load Capacity: The copper-lead intermediate layer dramatically increases the bearing’s ability to withstand the high cyclic loads generated by high-compression pistons, forced induction, or aggressive cam profiles, preventing fatigue failure and material spalling.
• Enhanced Debris Embedability: The softer overlay and intermediate layer act as a sacrificial buffer, trapping microscopic contaminants from assembly or normal wear before they can circulate and cause catastrophic damage to the crankshaft journals or other precision surfaces.
• Optimal Conformability for Longevity: Even with meticulous machining and alignment, minute deviations exist. The ACL bearing’s conformable surface ensures full-surface contact, distributing load evenly and preventing localized hot spots that lead to premature wear or seizure.
• Consistent Oil Film Retention: The precise surface finish and material properties promote the formation and maintenance of a robust hydrodynamic oil film, the essential barrier that separates the crankshaft from the bearing surface under operation, minimizing friction and wear.
• Direct OEM Fitment & Compatibility: Engineered as a direct replacement, the BC4060 set installs seamlessly into the F20C and F22C block, working perfectly with OEM or OEM-specification crankshafts, eliminating compatibility concerns and simplifying the build process.

Vehicle Fitment & Application Guidance

The BC4060 bearing set is specifically engineered for the Honda S2000’s four-cylinder engines. Its application is precise, catering to models equipped with the iconic high-revving powerplants.

Primary Vehicle Fitment:

• Honda S2000 (AP1): 2000-2003 models equipped with the 2.0L DOHC VTEC F20C engine.
• Honda S2000 (AP2): 2004-2009 models equipped with the 2.2L DOHC VTEC F22C1 engine.

Critical Application Notes: This set is for main bearings only. Always perform accurate micrometer measurements of your crankshaft journals and corresponding bore measurements in the block to verify the correct standard size is required. Final assembly must include precise plastigage measurement to confirm oil clearances are within factory specification, typically between 0.0008″ – 0.0016″ (0.020mm – 0.041mm) for these engines, though always consult the factory service manual for the exact, model-year-specific tolerance. For a deeper technical dive into the importance of bearing clearances and measurement techniques in performance engines, consult this authoritative resource from Engine Labs on bearing selection and clearance.

Technical Specifications: BC4060 Bearing Set

The Final Verdict: A Non-Negotiable Component for a Serious Build

Selecting the BC4060 ACL Race Series Bearing Set is a declarative statement about the intent and integrity of your Honda F20C/F22C engine project. It represents a rejection of commodity-grade parts in favor of motorsport-derived engineering. Whether you are executing a meticulous refresh of a high-mileage S2000 engine, building a naturally aspirated track weapon that lives at 8,000 RPM, or assembling a forced induction monster, the foundation must be unshakeable. These bearings provide that foundation. They offer the increased durability and performance margin of a true race component without the complication of non-standard sizing, making them the intelligent, authoritative choice for the performance mechanic who values data-driven results over marketing hype. When your goal is not just power, but enduring and reliable performance, the choice is clear: build on the proven, tri-metal strength of ACL.