This ACL High Performance main bearing set is sized for a standard, unmachined crankshaft main journal on the Acura B17A1/B18A1/B18B1/B18C1/B18C5 VTEC and Honda K20A3/K20A2/K24A engine family, built with extra oil clearance for engines running higher oil volume/pressure or looser bearing clearances (common in turbocharged or high-RPM builds). Per ACL's own fitment data this bearing size is shared across the Acura Integra, RSX, and TSX, and the Honda Accord, Civic Si, CR-V, and Element.
Specifications:
- Type: Main Bearing Set
- Series: High Performance
- Size: Standard, Extra Oil Clearance
- Engine Fitment: Acura B17A1/B18A1/B18B1/B18C1/B18C5 VTEC / Honda K20A3/K20A2/K24A
- Part Number: 5M1959HX-STD
FAQ
What does "Extra Oil Clearance" mean?
Extra oil clearance bearings run a slightly looser clearance than standard, which some high-RPM, high-oil-volume, or turbocharged/nitrous applications prefer for additional oil flow and thermal margin. Use standard clearance unless your engine builder specifies extra clearance.
What engines does this main bearing set fit?
It's sized for the Acura B-series (B17A1, B18A1, B18B1, B18C1, B18C5 VTEC) and Honda/Acura K-series (K20A3, K20A2, K24A) engine family, as used in the Acura Integra, RSX, TSX and Honda Accord, Civic Si, CR-V, and Element.
Do I need rod bearings too?
Yes, this listing is for main bearings only. Rod bearings for this engine family are sold separately.
Is this a Standard size or an oversize bearing?
This is Standard size — sized for a stock, non-machined main journal — with extra oil clearance built in.
