V10 5.2 Audi R8 and Huracan ARP Main Stud Kit

PR Spec Audi and Lamborghini V10 5.2 ARP main stud kits help eliminate main cap walk/fretting and protect the threads in your engine block, a must have for any engine rebuild which requires a superior alternative to oem torque to yield bolts which are single use only. Add confidence in the strength of your engine build with the ARP main stud kit designed for your application

The precision J-form threads are rolled after heat-treat for much stronger threads than the competition. Kits come complete with hardened parallel-ground washers and high-quality nuts.

The above process gives them about 1000% (that’s 10 times) better fatigue strength than those studs that are threaded prior to heat-treat (a very common industry practice). It costs a lot more to do it this way, because it’s tough on tooling, but the results are well worth the extra effort.

ARP2000 is a heavily alloyed martensitic quench and temper steel, initially developed for use in steam power plants. As such it has excellent stability at high temperatures. But most important, ARP research discovered that in addition to temperature stability it has excellent notch toughness in the higher strength ranges and is alloyed to be tempered to Rc44/47. 8740 and 4340 can be tempered to the same hardness. But, the tempering temperature would yield material in the “temper brittle zone” (between 500° and 700°F), producing significant notch sensitivity. ARP2000 is tempered above that temperature range and has a strength between 200,000 and 220,000 psi.