Bolt & Nut Set, connecting rod

Original connecting rod bolts are often in need of improvement. They are the most important fastener in the engine as they hold together the entire rotating assembly. A broken bolt will lead to catastrophic engine failure and not something we take lightly.

We had our engineer make a new set of drawings which were then passed on to ARP. To fabricate our design, ARP selected a premium grade 8740 chrome moly alloy steel that had been heat treated to provide a tensile strength in the 200,000 psi range, with a hardness class of 12.9. Once the bolt was complete, they paired it up with a premium quality companion nut and included a packet of their Ultra Torque Assembly Lube to ensure accurate torque readings and assembly.

What we ended up with, is quite simply the best Connecting Rod Bolt and Nut Set available for the MG T-Series engine today.

Torque: ARP has determined that 32 ft-lbs with use of ARP Ultra Torque Assembly Lube is optimal.
Stretch: Stretch for these bolts will be 0.0065-0.0070” when properly tightened using the ARP Ultra Torque Assembly Lube.