ARP HEAD STUD KIT CUSTOM AGE 625 SUPRA 2JZ. If you dont know what these are then you've been under a rock for a while. The ARP custom age 625 head studs are the STRONGEST head studs out there for the Toyota Supra. They have MORE clamp force than the ARP L19 material. They have more clamp force combined with the Half inch head stud conversion AND the stock size L19 studs. These are the studs you need when pushing over 1600whp. Long gone are the days of needing to go half inch L19 studs and ALL the machine work required to your block, head and gasket. These drop straight into the factory size threads and away you go. Some of the big names in the USA use these very studs on there 1500 whp 2JZ MKIV Supras. Joel Grannas, Jessica Barton, Darin Dichiara and many more. Even our 1500bhp Future Motorsports Supra run these head studs.