ARP 209-4301 Head Studs for Opel Astra / Vectra / Calibra 2.0L 16V C20LET C20XE

Name: ARP 209-4301 Head Studs for Opel Astra / Vectra / Calibra 2.0L 16V C20LET C20XE

Brand: ARP

Part number: ARP-209-4301

Country of Manufacture: United States

It is no accident that virtually every top professional engine builder relies on ARP Pro Series head studs for their competition engines. Simply put, there is not a better stud system

on the market today. ARP uses premium grade 8740 alloy exclusively and a proprietary ARP2000 alloy, which are vastly superior to aircraft quality alloy steels. Additionally, each stud is placed vertically
in special fixtures and precisely heat-treated to 190,000 psi for the 8740 material and 220,000 psi for the ARP2000 material. This procedure ensures complete heat penetration, and the results are far superior to inferior studs from other manufacturers who simply dump parts in a basket and hope for the best. Importantly, inferior studs are not even centerless ground; the material is rolled into bar stock (usually prior to heat treating, when the material is easier to machine). Because ARP studs are manufactured to such exacting tolerances, you will notice that gaskets and cylinder heads literally glide into place and are perfectly aligned – something that does not happen with inferior head studs.
Using studs makes it much easier to assemble an engine (especially a competition engine that must be frequently and quickly serviced), as the cylinder head and gasket are assured of proper alignment.

Studs also provide more accurate and consistent torque loading. Here's why: when you use bolts to secure the head, the fastener is "twisted" as it is torqued. So, the bolt reacts to two different forces simultaneously. A stud must be installed in a "relaxed" mode - never forcefully tighten it using a jam nut. If everything is correct, the stud should install by hand. Then, when torquing the nut, the stud will stretch
only in the vertical axis. Remember that a shorter stud with an undercut will have a stretch rate similar to a longer, standard shank stud. This provides a more even clamping force on the head.

ARP® - Automotive Racing Products is a manufacturer of fasteners/bolts found in engines and drivetrain systems, from OEM replacement parts to specialized hardware for racing applications. ARP is a world leader in fastener technology. These range from high-performance, quality OEM replacement parts to specialized hardware for Formula 1, IndyCar, NASCAR, NHRA drag racing, and marine applications. To ensure optimal quality control, ARP has become exceptionally self-sufficient and now controls every aspect of the manufacturing process. This is how ARP has managed to establish a reputation as a leading brand in the market.