ARP reinforced main studs, AUDI S4 RS4 B5 2.7T 30V (AGB, ASJ, AZB, AZR)

This kit of ARP reinforced main studs for the AUDI 2.7T 30V engine is made up of 16 ARP studs, 16 ARP nuts and 4 ARP bolts.

Find the assembly instructions in the "Download" tab above.

Coming from the aerospace industry, Gary Holzapfel created the ARP (Automotive Racing Products) brand in the early 1970s to answer a major problem in motorsport: engine failure caused by bolts and studs that were not strong enough. At the time, no manufacturer was able to meet this need. Today ARP offers thousands of references across different ranges and types of products such as head bolts, main bearing bolts and con rod bolts. Depending on the application, ARP offers different ranges (materials) of hardware:

• 8740: a chrome-molybdenum steel with standard resistance properties fully suited to prepared engines. This steel offers a tensile strength of between 1240 and 1447 N/mm².
• ARP2000: stronger than 8740, the ARP2000 alloy can withstand clamping/tensile loads of up to 1516 N/mm². This range of hardware is frequently used on track and drag cars and can be used with hydrogen.
• L19: a high quality treated steel offering significantly higher tensile and fatigue resistance properties than the 8740 and ARP2000 ranges. Its tensile strength can reach up to 1792 N/mm². This material is more sensitive to corrosion and must therefore stay oiled and not be exposed to moisture. Hydrogen use is not recommended with this range.
• CA625+ (Custom Age 625 Plus): this "super-alloy" has significantly superior technical properties while being resistant to corrosion and oxidation. Its tensile strength can reach up to 1930 N/mm².

All ARP hardware is designed and manufactured in the United States. The manufacturing of ARP hardware starts with cold or hot forging, then a heat treatment (different depending on the range) is applied and shot peening is then carried out to eliminate irregularities. Precision grinding then follows to achieve perfect concentricity, before the thread is cut. Finally, a coating is applied, such as black chrome-molybdenum oxide or stainless steel polishing, depending on the product range.

Each kit is supplied with assembly lubricant and instructions stating:

• Installation steps
• The tightening torque
• The tightening procedure