ACL 4B1630H-STD Race Rod Bearing Set Standard Nissan CA18DET CA16 CA18 CA20

Vehicle Fitment

• Nissan CA16 - 1.6L (1598cc) SOHC 8v Inline-4 (Naturally Aspirated)
• Nissan CA16DE - 1.6L (1598cc) DOHC 16v Inline-4 (Naturally Aspirated)
• Nissan CA18 / CA18E - 1.8L (1809cc) SOHC 8v Inline-4 (Naturally Aspirated)
• Nissan CA18DE - 1.8L (1809cc) DOHC 16v Inline-4 (Naturally Aspirated)
• Nissan CA18ET - 1.8L (1809cc) SOHC 8v Inline-4 Turbo
• Nissan CA18DET - 1.8L (1809cc) DOHC 16v Inline-4 Twin-Cam Turbo
• Nissan CA20 / CA20E - 2.0L (1974cc) SOHC Inline-4 (Naturally Aspirated)
• Nissan CD17 - 1.7L Inline-4 Diesel

Fitment Notes

• Standard (STD) crankshaft rod journal diameter - for use with stock or unworn crankpins at factory diameter only. For reground crankshafts, use 4B1630H-.025 (+0.025mm), 4B1630H-.25 (+0.25mm), or 4B1630H-.50 (+0.50mm) as appropriate.
• An HX extra-clearance variant (4B1630HX-STD) is also available for builders targeting approximately 0.025mm (0.001") additional running clearance at standard journal diameter without crankshaft grinding.
• Always measure crankshaft rod journal diameter with a micrometer before selecting bearing size. Confirm actual clearance with Plastigage or a dial bore gauge after assembly.
• Sold as a complete set of 8 bearing shells - sufficient for one full 4-cylinder engine build.

Features

• Tri-metal construction: copper-lead alloy lining bonded over a hardened steel backing, with a high-strength overlay plate - engineered for the high-RPM and forced-induction demands of built CA-series Nissan engines, particularly the CA18DET.
• Hardened steel backing on all rod bearings improves structural support of the bearing lining and maintains crush under high sustained loads and temperatures.
• High-strength overlay plate with reduced thickness provides improved fatigue resistance compared to OEM-spec bearings - critical in turbocharged CA18ET and CA18DET builds at elevated boost pressures.
• Increased bearing crush and tighter wall tolerances ensure consistent, secure seating in the connecting rod housing bore, reducing the risk of bearing spin.
• Enlarged ID chamfers on bearing edges accommodate the larger fillet radii found on performance and aftermarket CA-series crankshafts.
• 3/4-groove design optimizes oil supply to the rod journal and maximizes load-carrying surface area across the bearing face.
• Elimination of flash plating on bearing backs improves heat transfer and maximizes grip between the bearing shell and the rod housing bore.
• Increased eccentricity compensates for bore distortion at high RPM and assists in the formation of a stable hydrodynamic oil film under load.

Specifications

• Part Number: 4B1630H-STD
• Product Line: ACL Race Series
• Application: Connecting Rod Bearings
• Engine Compatibility: Nissan CA16, CA16DE, CA18, CA18E, CA18DE, CA18ET, CA18DET, CA20, CA20E, CD17
• Crankshaft Size: Standard (STD - Unground)
• Shaft (Crankpin) Diameter: 44.961-44.974mm (1.7701-1.7706 in)
• Tunnel (Housing Bore): 48.000-48.013mm (1.8898-1.8903 in)
• Maximum Wall Thickness at Crown: 1.492mm (0.0588 in)
• Maximum Overall Length: 18.6mm (0.732 in)
• Bearing Material: Tri-Metal Copper-Lead Alloy / Hardened Steel Backing
• Quantity: Set of 8 Shells (complete engine set)

Included Components

• 8x Race Series Connecting Rod Bearing Shells - Standard Size

Product Description

The ACL Race Series 4B1630H-STD connecting rod bearing set is the standard-size performance replacement for Nissan's CA-series inline-4 engine family - covering the CA16, CA18, CA18DET, CA20, and related variants that powered some of the most iconic JDM and export performance cars of the 1980s and early 1990s, including the Silvia S12 and S13, the 180SX, and the European 200SX. Designed for use with stock-diameter, unground crankshaft rod journals, this is the standard selection for fresh engine builds using a serviceable factory crankshaft confirmed to be within standard dimensional tolerance.

The CA18DET in particular remains one of the most rebuilt and modified engines in Japanese performance history, and ACL Race Series bearings are a standard specification for serious CA18DET rebuilds at any power level. Built on ACL's proven tri-metal platform, these bearings deliver superior fatigue resistance, bearing retention, and oil film stability over OEM shells. For builders targeting increased running clearance at standard journal size, the HX variant (4B1630HX-STD) is available separately. Always confirm clearances at assembly with precision measurement before final torque. Sold as a complete set of 8 shells for one engine.