ARP uses a premium grade 8740 alloy, rated far superior to 'aircraft' quality, for their Pro Series cylinder head studs.
Each stud is placed in special racks vertically and heat-treated precisely to 200,000 psi for complete heat penetration.
The studs are then ground centerless to achieve perfect concentricity, unlike lesser quality studs.
Due to the exacting tolerances in manufacturing ARP studs, gaskets and cylinder heads will glide into position and align perfectly—something that won't occur with inferior quality head studs.
After heat-treat, these studs are thread rolled, resulting in about 1000% (ten times) better fatigue strength than studs threaded prior to heat-treat, a common industry practice.
Although this method is more costly due to its impact on tooling, the results justify the extra effort.
This cylinder head stud kit includes premium quality parallel ground washers and compact 12-point style nuts for select Chevrolet big block applications (cast OEM, Aluminum factory heads, also early Bowtie).
