Mitsubishi 4G63 '94 UP M11 Head Stud Kit

ARP® uses a premium grade 8740 chromoly that is rated far superior to to "aircraft quality". Then, each stud is placed vertically in special racks and precisely heat-treated to 190,000 psi. This procedure ensures complete heat penetration and the results are far superior to those lesser quality studs from other manufacturers who just dump pieces in a basket and hope for the best.

Following heat-treat, each stud is centerless ground to make it as close to perfectly concentric as possible. This procedure involves about ten very slight cuts and results in an exceptionally straight part. It s important to note that lesser quality studs are not even centerless ground the material is thread rolled in bar stock form (mostly before heat-treat, when the material is easier to machine). Because ARP® studs are manufactured to such exacting tolerances, you will note that gaskets and cylinder heads literally glide into position and are perfectly aligned something that won t happen with inferior quality head studs. ARP® studs are thread rolled after heat-treat, which gives them about 1000% (thats ten times) better fatigue strength than those studs 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 well worth the extra effort.

Kit Instructions