ACL Race Conrod Bearings Honda F20C / F22C / H22A – 4B1912H-STD

ACL Race Conrod Bearings – Honda F20C / F22C / H22A (4B1912H-STD, Standard Size)

ACL Race rod bearings 4B1912H-STD are a performance-oriented alternative to Honda OEM bearings for the F20C, F22C and H22A engine families. Standard (STD) size — journal diameter 48 mm, tunnel 51.004–51.024 mm, wall thickness up to 1.496 mm, width 19.4 mm. Identical upper and lower halves; no oil hole. Weight: 0.17 kg per set.

ACL Race bearings are manufactured to tighter tolerances than OEM and use a high-load tri-metal construction, making them a popular choice for engines running higher power levels, forced induction, or frequent high-rpm use. They are a direct fit — no machining required at standard size.

Applications

Technical Specifications

OEM Reference Numbers

These ACL bearings cross-reference the following genuine Honda part numbers:

• 13211-P13-014, 13212-P13-014, 13213-P13-014, 13214-P13-014
• 13215-P13-014, 13216-P13-014, 13217-P13-014
• 13211-PCX-003, 13212-PCX-003, 13213-PCX-003, 13214-PCX-003
• 13215-PCX-003, 13216-PCX-003, 13217-PCX-003

When to Replace Main Bearings

• Knocking or rumbling noise from the bottom end, especially under load or at low rpm
• Significant drop in oil pressure (below factory spec at operating temperature)
• Engine teardown for rebuild — always replace bearings regardless of visible wear
• Metal particles found in oil or on the drain plug magnet
• Crankshaft polishing or regrind — replace with the appropriate undersize bearings

Installation Tips

• Measure crankshaft journal diameter and main bore before fitting — confirm STD size is correct for your application.
• Check bearing clearance with Plastigauge before final assembly; ACL Race bearings are designed for tighter clearances than OEM.
• Clean all oil passages in the block and crankshaft thoroughly before installation.
• Lubricate bearing surfaces with clean engine oil or assembly lube before fitting the crank.
• Torque main cap bolts in sequence and to the manufacturer's specification for your specific engine variant.
• These bearings have no oil hole — ensure correct orientation as specified in your engine's workshop manual.

FAQ – ACL Race Rod Bearings Honda 4B1912H-STD

Are ACL Race bearings suitable for a standard road engine, or are they only for race builds?
ACL Race bearings work well in both stock and performance builds. Their tighter manufacturing tolerances benefit any engine, but they are especially popular in boosted, high-revving, or track-driven applications where OEM bearings may not handle the increased loads.

Is STD the only available size for 4B1912H?
ACL produces this bearing set in standard (STD) size and several undersizes for reground crankshafts. If your crank has been ground, you will need the correct undersize variant — measure the journal before ordering.

Do ACL Race bearings require a specific oil viscosity?
ACL does not mandate a specific oil viscosity, but for performance applications running tighter clearances, many builders prefer a slightly higher-viscosity oil (e.g. 10W-40 or 10W-50) compared to the OEM recommendation. Follow your engine builder's advice based on the actual measured clearances.

How does ACL compare to genuine Honda bearings for a stock rebuild?
For a standard road rebuild, both are viable options. ACL Race bearings offer tighter dimensional tolerances and a tri-metal construction that handles higher loads, so many engine builders choose them even for OEM-spec rebuilds as a straightforward quality upgrade over the original parts.