ACL 4B1946H-STD Race Series Rod Bearing Set STD for Honda/Acura B16A B17A B18A

Vehicle Fitment

• 1988-2001 Honda Civic / CRX (B16A swap) - 1.6L DOHC VTEC (B16A1, B16A2, B16A3)
• 1999-2000 Honda Civic Si - 1.6L DOHC VTEC (B16A2)
• 1993-1997 Honda Civic del Sol VTEC - 1.6L DOHC (B16A2, B16A3)
• 1990-1993 Acura Integra RS/LS/GS - 1.8L DOHC Non-VTEC (B18A1)
• 1992-1993 Acura Integra GS-R - 1.7L DOHC VTEC (B17A1)
• 1994-2001 Acura Integra RS/LS/GS - 1.8L DOHC Non-VTEC (B18B1)
• 1997-1998 Honda CR-V LX - 2.0L DOHC (B20B4)
• 1999-2001 Honda CR-V LX/EX - 2.0L DOHC (B20B4, B20Z2)

Fitment Notes

• Compatible engine codes: B16A1, B16A2, B16A3, B17A1, B18A1, B18B1, B18B2, B20B4, B20Z2
• Standard (STD) size - fits standard crankshaft journal dimensions; measure journals before ordering
• Does not fit B18C VTEC engines (GS-R, Type R) - use ACL 4B1925H for B18C applications
• Does not fit B-series SOHC (D-series) engines
• Full 180° grooved upper half with matching partial groove in lower half
• Sold as a set of 4 rod bearing shells (2 halves x 4 cylinders)
• Always verify journal dimensions with a micrometer before ordering

Features

• ACL Race Series tri-metal construction - high-strength overlay plate with reduced thickness for superior fatigue resistance at high RPM
• Hardened steel backing on all shells - improves lining support and positive bearing retention in the rod housing
• Increased bearing crush over OEM - ensures secure shell seating under high-load, high-boost conditions
• No flash plating on the back - maximizes heat transfer through the bearing and increases grip on the housing bore
• Full 180° grooved upper with tapered groove run-out - reduces interruption to big-end oil supply and avoids pressure pulsing and cavitation
• Increased eccentricity - compensates for rod bore distortion at elevated RPM and promotes a stable hydrodynamic oil film
• Excellent seizure resistance and embeddability - handles contaminated oil and extreme operating conditions better than OEM
• Manufactured to micron-level tolerances for consistent oil clearances across all four journals

Specifications

• Part Number: 4B1946H-STD
• Size: Standard (STD)
• Bearing Series: Race Series (H)
• Bearing Material: Tri-Metal
• Compatible Engine Displacements: 1.6L (1595cc), 1.7L (1678cc), 1.8L (1834cc), 2.0L (1973cc)
• Configuration: 4-cylinder inline (DOHC B-Series)
• Groove Pattern: Full 180° grooved upper / partial grooved lower with tapered run-out
• Quantity: Set of 4 bearing shells
• Warranty: ACL standard manufacturer's warranty

Included Components

• 4x ACL Race Series Rod Bearing Shells (Standard Size)

Product Description

The ACL 4B1946H-STD is a Race Series tri-metal connecting rod bearing set engineered for Honda and Acura B-series engines, covering the B16A, B17A1, B18A1, B18B1, and B20 engine families used in the Civic Si, Civic del Sol, CRX, Acura Integra, and Honda CR-V from 1988 through 2001. At standard size, these bearings fit crankshafts with unmachined, standard-dimension rod journals - making them the correct choice for fresh rebuilds or engines with journals that measure within OEM specification. Journal size should always be verified with a micrometer before ordering.

ACL Race Series bearings improve on OEM in every area critical to performance use: hardened steel backing for positive retention, increased crush to prevent shell movement, no flash plating on the back for better heat transfer, and increased eccentricity to compensate for bore distortion at high RPM. The full 180° grooved upper half with tapered groove run-out optimizes oil delivery to the rod journal while avoiding pressure pulsing and cavitation under sustained high-revving conditions. These characteristics make the 4B1946H-STD the preferred rod bearing for naturally aspirated, turbocharged, and boosted B-series builds where reliability and longevity under load are non-negotiable. Note: for B18C VTEC applications (GS-R, Type R), use ACL part 4B1925H instead.