ARP Main Studs 2.8/2.9 12V/24V VR6 R32

This kit of reinforced main studs for VR6 and R32 engines is made up of 14 ARP studs, 14 ARP washers and 14 ARP nuts.

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

Below (click on the image) you will find the big end bearings and the main bearings for the VAG VR6 R32 engine:

Gary Holzapfel came from the aerospace industry and created the ARP brand (Automotive Racing Products) 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 that need. Today ARP offers thousands of part numbers across several ranges and product types such as head bolts, main studs 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 between 1240 and 1447 N/mm2.
• ARP2000: stronger than 8740, the ARP2000 alloy withstands clamping and tensile loads of up to 1516 N/mm2. This range is widely used on track and drag cars and can be used with hydrogen.
• L19: a high grade treated steel offering tensile and fatigue strength properties clearly above the 8740 and ARP2000 ranges. Its tensile strength reaches up to 1792 N/mm2. This material is more sensitive to corrosion, so it must be kept oiled and away from moisture. Hydrogen is not recommended with this range.
• CA625+ (Custom Age 625 Plus): this super alloy has clearly superior technical properties while resisting corrosion and oxidation. Its tensile strength can reach 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 (different for each range) is applied and shot peening removes any irregularity. Precise grinding follows to obtain perfect concentricity, then the thread is produced. Finally comes the finish, where a coating such as black chrome molybdenum oxide or stainless steel polishing is applied depending on the product range.

Every kit is supplied with an assembly grease and an instruction sheet giving:

• The installation steps
• The torque figure
• The tightening procedure