Uprated ARP main studs, AUDI RS3 TTRS 2.5 TFSI DAZA DNWA

This uprated ARP main stud kit for the AUDI RS3 and TTRS 2.5 TFSI DAZA DNWA engine consists of 12 ARP studs, 12 ARP washers and 12 ARP nuts.

The fitting instructions are in the "Download" tab above.

Gary Holzapfel came from the aerospace industry and founded ARP (Automotive Racing Products) in the early 1970s to answer a major problem in motor sport: engine failure caused by bolts and studs that were simply not strong enough. At the time no manufacturer was able to meet that need. ARP now offers thousands of part numbers across several ranges and product types, among them cylinder head bolts, main bearing bolts and con rod bolts. Depending on the application, ARP offers several ranges (materials) of fasteners:

• 8740: a chrome-molybdenum steel with standard strength properties, entirely suitable for prepared engines. This steel offers a tensile strength of between 1240 and 1447 N/mm2.
• ARP2000: stronger than 8740, the ARP2000 alloy will take clamping and tensile loads of up to 1516 N/mm2. This range is widely used on circuit and drag cars and can be used with hydrogen.
• L19: a treated high grade steel offering tensile and fatigue strength properties well above the 8740 and ARP2000 ranges. Its tensile strength reaches up to 1792 N/mm2. This material is more prone to corrosion and must therefore be kept oiled and away from moisture. Hydrogen is not recommended with this range.
• CA625+ (Custom Age 625 Plus): this "super-alloy" offers markedly higher technical properties while resisting corrosion and oxidation. Its tensile strength reaches 1930 N/mm2.

All ARP fasteners are designed and manufactured in the United States. Production starts with cold or hot forging, then a heat treatment is applied, which differs from range to range, and shot peening follows to remove any irregularity. Precision grinding then gives perfect concentricity, after which the thread is cut. Last comes the finish, where a coating is applied: chrome-molybdenum black oxide or stainless steel polishing, depending on the range.

Every kit is supplied with assembly lubricant and instructions setting out:

• The fitting steps
• The tightening torque
• The tightening procedure