Description
This ARP Main Stud Kit is designed to replace BMW 11111735525 for the M50/M52/S50/S52 engines that were used in a variety of BMW models.
One significant advantage of these main studs is their ability to prevent main cap walk, which can occur when the main caps shift or move out of position, potentially causing damage to the engine. In addition, ARP Main Studs can safeguard the threads of your engine block, providing an extra layer of protection against potential damage.
When opting for main studs instead of factory bolts, it's important to note that the engine builder should mic the bores. Using studs may require a line hone to ensure proper fitment and alignment. A line hone is a machining process that can be used to resize and reshape the main bearing bores, ensuring that they are perfectly round and concentric. This is crucial for ensuring proper oil clearance and preventing premature bearing wear. By mic'ing the bores and performing a line hone if necessary, engine builders can ensure that the main studs are installed correctly and that the engine will perform reliably and at its best.
Installation Instructions:
To ensure accurate torque readings and proper thread engagement, thoroughly clean all threads in the engine block. If necessary, use an ARP chaser to chase the threads.
Before installing any hardware, carefully inspect and clean it for defects, shipping damage, and proper fit, length, and dimension.
Gently screw the main studs into the engine block by hand until they are snug.
Install the main caps, checking for any binding or misalignment.
Apply ARP Ultra-torque fastener assembly lubricant to the threads of the studs, nuts, and washers. Install the washers and nuts onto the studs and tighten them by hand. It is highly recommended to use the ARP Ultra-torque fastener assembly lubricant provided with the kit, as it provides consistent clamping force and reduces friction on the studs. Do not use motor oil or other low-quality lubricants.
PRELOAD (TORQUE) RECOMMENDATIONS
7. Following the manufacturer-recommended torque sequence tighten the nuts in steps 1-3
Step 1: Tighten to 20 ft-lbs.
Step 2: Tighten to 40 ft-lbs.
Step 3: Tighten to 60 ft-lbs.
With the included ARP Ultra-Torque fastener assembly lubricant