BMW 2.5L M54 (325) H-Beam Connecting Rods are crafted from 4340 high tensile steel, designed for high performance and extreme durability. The bushings are made from aluminum-silicon/bronze material with a radial groove acting as an oil reservoir. These rods feature a "Ribbed pin end" to minimize pin end distortion under heavy inertial loads while saving excess weight. They are shot peened to relieve stress and undergo multi-stage heat treatment to increase rigidity. The production process ensures tight tolerances for perfect fitment and optimized oil clearances, with controlled bend and twist. Each rod includes ARP 2000 cap fasteners rated at 220,000 psi, with an optional upgrade to ARP L19 material rated at 260,000 psi. The kit is supplied with ARP moly and full fitting instructions.

Additional Machining Processes

• Dowel sleeves for perfect fit and accurate re-assembling
• Lipped Cap Relief for improved big-end integrity at extreme application
• Grooves in Thrust Face for weight reduction

Technical Features of ZRP Connecting Rods

• Two-Piece forging for great strength
• Shot Peening for improved fatigue life
• Magnaflux Inspection ensures high-quality material consistency
• Double ribbed caps for added support
• Multi Stage Heat Treatment for maximum strength, dimensional stability, and fatigue life
• CNC machining for superior tolerances, precise to 0.0002"
• Center to center maintained under .001" tolerance
• Finite Element Analysis (FEA) for stress analysis of con rods
• Optimal balancing for weight matched sets of ± 1 gram