ARP Connecting Rod Bolt Kit 201-6201

The ARP Pro Series Rod Bolt Kit is engineered for BMW S50US and S52 engines, providing superior strength and reliability for high-performance builds. This kit replaces BMW part #11241739729 and includes 44mm bolts. Some M50 engines may also use this shorter 44mm bolt, but most require the longer 53mm version (ARP #201-6301).

Each ARP rod bolt is precision CNC-machined to exacting specifications, ensuring optimal performance under extreme conditions. Unlike standard bolts, ARP rod bolts are thread rolled after heat treatment, significantly increasing fatigue strength—up to ten times greater than bolts threaded before heat treatment. This advanced process enhances durability, making them ideal for high-compression and high-stress engine applications.

Designed to outperform OEM fasteners, ARP Pro Series rod bolts provide the reliability and strength needed for demanding engine builds, ensuring long-term performance and security.

Installation Instructions:

1. Ensure there is an adequate chamfer around the bolt hole on the connecting rod bolt hole on the connecting rod cap to clear the radius under the head of the bolt
2. Use ARP Ultra-Torque Fastener Assembly Lubricant to lubricate the threads of the bolt and the under head of the bolt. Then install the bolts and tighten them them hand tight. 
3. ARP recommends using the Stretch Method when tightening rod bolts. Following the instructions for using a stretch gauge, stretch the bolts to 0.0070 - 0.0075. 
4. If you do not have a stretch gauge, torque the bolts to 40 ft-lbs using ARP Ultra-Torque Fastener Assembly Lubricant.
5. The connecting rods should always be re-sized after new rod bolts are installed. 
6. A log should be kept on the original non-torqued length of each bolt. Bolts that have any permanent deformation or have increased in non-torqued length by more than 0.001 inch should be replaced.