ZRP Connecting Rods I-Beam HD Series for Honda B18C 1.8

ZRP Heavy Duty I-Beam Connecting Rods for Honda B18C

The ZRP Heavy Duty I-Beam Connecting Rods are engineered specifically for high horsepower and high-boost Honda B18C applications, making them an ideal choice for turbocharged engines and extreme performance builds.

Manufactured from premium 4340 high-tensile steel, these connecting rods feature a specially optimized I-beam design that delivers exceptional rigidity, strength, and long-term durability under extreme loads. The rods undergo multi-stage heat treatment and shot peening to relieve internal stress, enhance fatigue resistance, and ensure maximum structural integrity.

The AMPCO 18 bronze bushings provide outstanding resistance to wear and fatigue. Each bushing includes a radial oil groove, acting as an oil reservoir to improve lubrication and reliability at high RPM. Tight production tolerances guarantee precise fitment, optimal oil clearances, and strict control of bend and twist.

Every set is CNC-machined to ultra-tight tolerances (down to 0.0002”) and fully inspected using Magnaflux testing to ensure material consistency and the highest quality standards. Finite Element Analysis (FEA) is used during design to optimize stress distribution and performance.

Each connecting rod is supplied with 3/8” ARP 2000 cap fasteners rated at 220,000 psi, with ARP L19 (260,000 psi) available as an optional upgrade. The kit includes ARP moly lubricant and full installation instructions.

Additional Machining Features

• Dowel sleeves for precise fitment and accurate reassembly

• Lipped cap relief for improved big-end integrity in extreme applications

• Thrust-face grooves for weight reduction

• Double-ribbed caps for added strength and stability

Technical Specifications

• Engine Compatibility: Honda B18C1 / B18C2 / B18C5 / B18C7

• Displacement: 1.8L B18

• Recommended Use: Turbo applications

• Rod Shape: I-Beam

• Center-to-Center Length: 138.00 mm

• Wrist Pin Size: 21.00 mm

• Big End Bore: 48.00 mm

• Big End Width: 21.79 mm

• Bolt Size: 3/8”

• Fastener Grade: ARP 2000

• Weight: 534 g per rod

• Weight Matching: ±1 gram

• Set Includes: 4 connecting rods

• Series: Heavy Duty