M104 Forged Piston and Connecting Rod Kit

The Hench Performance M104 kit is a comprehensive engine upgrade set engineered for Mercedes-Benz M104 3.2L engines, and also compatible with specific Roewe, SsangYong, Heuliez, and Status & Class models. The kit features H-beam forged connecting rods crafted from durable 4340 alloy, complete with 3/8″ bolts and a choice of C-C lengths (143.00mm, 144mm, 145.00mm, or 147.00mm, please specify when ordering). Accompanying these are forged pistons made from 4032 alloy, featuring a 90.05mm bore diameter (0.15mm oversized) and a 10:1 compression ratio. The set also includes dual valve springs made from a super clean alloy, designed to fit all M104 engines with stock or straight valve springs. Additionally, lightweight Ti-64 titanium retainers are included to reduce weight and improve response and high RPM capability. These retainers reduce weight from the stock 20.8g to 11.8g. Note that the titanium retainers do not fit conical valve springs from M104.942/995 engines. The connecting rods feature two-piece forging, shot peening for fatigue life, bronze bushings, Magnaflux inspection, multi-stage heat treatment, and CNC machining for superior tolerances, with weight-matched sets of ±1 gram. The pistons are phosphate coated for enhanced lubrication and feature pin oiling for extended lifetime at high temperatures and RPMs. The full kit contains 6 pistons, 6 piston pins, 12 pin locks, 6 piston rings, 6 connecting rods, 12 bolts, 24 dual valve springs, and 24 titanium retainers.