ARP is the leader in fastener technology. These ARP exhaust studs are stainless steel and replace the factory 2 studs and 3 bolts.
2ZZ cylinder head is aluminum and the factory bolts are known the be at the root of the problem of stripping out the soft aluminum threads. These studs will help prevent that. If you're replacing the header on your 2ZZ powered Lotus or building a motor, take the opportunity to upgrade the header hardware at the same time!
Installation is simple. Double nut the factory 2 studs or use a stud removal tool to remove the outer two studs. Install the ARP studs with an allen wrench until they're snug. Simply install the header and torque the ARP 12pt nuts to 40-45ftlbs, dry.