Engines and Components› Engine Bearings

ACL Race

Race Engine Bearing Kit Trimetal

$119.99

SKU: 4B1946H-STD + 5M1959H-STD

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Special Order
Ships in 4–6 weeks
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$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

This kit includes main bearings (part # 5M1959H-STD), rod bearings (part # 4B1946H-STD), and thrust washers (part # 1T1957-STD).

These bearings are constructed from a Trimetal material, offering drivers the expected performance from high-performance engine bearings. They are manufactured to exacting tolerances to ensure a reliable fit and maintain consistent clearances. The thrust washers specifically help support the crankshaft and withstand stresses from clutch and flywheel operation.
Show original supplier description
This comprehensive kit includes main bearings (part # 5M1959H-STD), rod bearings (part # 4B1946H-STD), and thrust washers (part # 1T1957-STD), all designed to work in conjunction for optimal engine function. Constructed from high-performance Trimetal material, these bearings provide the reliability and durability expected in high-stress environments. The manufacturing process emphasizes exacting tolerances and wall thickness accuracy, ensuring a precise fit and consistent oil clearances critical for engine longevity. The included thrust washers are vital for maintaining crankshaft stability and managing the stresses associated with clutch and flywheel operations. This set is recommended for a range of Honda B-Series engines, including B16A, B17A1, B18A1, B18B, B18B2, B20B, and B20Z variants. Some applications also extend to K-Series and D-Series engines, depending on the specific component and engine configuration. It's crucial to verify compatibility with your specific engine code for optimal performance and fitment.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandACL Race
Part Number4B1946H-STD + 5M1959H-STD
CategoryEngines and Components
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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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