ARP uses a premium grade 8740 alloy that is rated far superior to aircraft quality. Each stud is placed vertically in special racks and precisely heat-treated to 200,000 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 centreless 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 is important to note that lesser quality studs are not even centreless ground.
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.
ARP studs are thread rolled after heat-treat, which gives them about 1000% (that is 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 is tough on tooling, but the results are well worth the extra effort.
You will also note that ARP offers specially undercut studs for several engines. This procedure (done only to the shorter studs) more equalizes the stretch of both studs, which makes for a more consistent clamping force and one that compensates for head gasket compression when the cylinder heads are installed. This helps prevent blown head gaskets, and assures optimum engine sealing!
You will not find a better quality stud on the market from any other source. Look for ARP stamped on each stud as your assurance of quality.
Clearly, ARP Head Stud/Bolt Kits are the best on the market today, and the favourite of leading professional engine builders in all forms of racing.
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