ARP uses a premium grade 8740 alloy, rated far superior to 'aircraft' quality, for their cylinder head studs Pro Series.
Each stud is placed vertically in special racks and heat-treated precisely to 200,000 psi for complete heat penetration.
The studs are centerless ground to make them as close to perfectly concentric as possible, unlike lesser quality studs.
Because ARP studs are manufactured to such exacting tolerances, you will note that gaskets and cylinder heads glide into position and are perfectly aligned -- something that won't happen with inferior quality head studs.
By being thread rolled after heat-treat, these studs have about 1000% (that's ten times) better fatigue strength than those 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 worth the extra effort.
This cylinder head stud kit comes complete with premium quality parallel ground washers and hex style nuts conventional.
