ARP Triumph/Spitfire 12pt Head Stud Kit

ARP uses 8740 chromoly steel for these head stud kits, a well-known material for its strength and durability. This particular kit is designed for Triumph and Spitfire engines, featuring a 12-point nut design that makes them easier to torque down compared to standard hex nuts, especially in tight engine bays. Using head studs instead of bolts is a common practice when rebuilding or modifying these engines because they provide more consistent clamping force on the cylinder head. This improved clamping helps prevent head gasket leaks, which can be a common issue with these older engines, especially if you're pushing more power or dealing with higher operating temperatures.

The studs themselves are rolled, not cut, which strengthens the material along the threads and reduces stress risers. This means they're less likely to stretch or fail under the high clamping loads required for proper head gasket sealing. ARP includes all the necessary nuts and washers with the kit, and they are also made from high-strength materials to match the studs. When installing, make sure to follow ARP's specific instructions regarding thread sealer and torque sequences to get the most out of this well-built kit.