Subaru EJ20 / EJ205 / EJ25 HD Series ZRP Connecting Rods

The I-Beam “Heavy Duty” series connecting rods for Subaru 2.0L EJ20 and 2.5L EJ25 engines are designed for high-horsepower/high-boost applications. Made from the finest raw material, 4340 high-tensile steel, they feature a specially optimized shape for high performance and extreme durability. The bushings are made from AMPCO 18 material for excellent resistance to wear and fatigue, with a radial groove that acts as an oil reservoir. They are shot-peened to relieve stress in the material and undergo multistage heat treatment to increase rigidity. Tight production tolerances ensure a perfect fit while optimizing oil clearances. Bending and twisting are tightly controlled. Each rod includes 3/8-inch ARP 2000 cap fasteners rated at 220,000 psi; optional ARP L19 material rated at 260,000 psi is available as an upgrade, and the whole kit is supplied with ARP moly and complete fitting instructions. Additional machining processes

• Dowel sleeves for perfect fit and accurate reassembly
• Lipped cap relief for improved big-end integrity in extreme applications
• Grooves in the thrust face for weight reduction

Technical Features of ZRP Connecting Rods

• Two-piece forging for great strength
• I-beam shape for extra rigidity
• Shot peening for improved fatigue life
• Magnaflux inspection guarantees that the consistency of the forged material meets our high-quality standard
• Double-ribbed caps for added support
• Multistage heat treatment for maximum strength, dimensional stability, and fatigue life.
• CNC machining for superior tolerances, precise to as much as 0.0002"
• Center-to-center length is maintained within a .001" tolerance
• Finite Element Analysis (FEA): computer-generated stress analysis of connecting rods
• Optimal balancing for weight-matched sets within ± 1 gram