HPR Audi 2.5L Diesel Crankshaft Bolt (95.5mm crankshafts)

This is a highly engineered and meticulously crafted M18 bolt for those building a high horsepower stroker engine out of their old 5-cylinder.

This bolt will ONLY fit the diesel crankshafts as the threads are deeply recessed into the crankshaft.  These will not work for your 2.5L eurovan gas engines.

The bolt is made from 8740 chromoly-steel.  The threads are form rolled, NOT cut.  Bolts are then heat treated to a very specific rockwell hardness and tested.  Finally, they are zinc plated for corrosion resistance (they are cleaned in hydrochloric acid and baked prior to plating to prevent hydrogen embrittlement).  These bolts are VASTLY over-engineered to prevent any issues.

These bolts are reusable and do not lose their strength.  These were purpose designed for maximum safety and reliability regardless of torque and horsepower levels.

You will not find something stronger than this out there.

The bolts have been proof-loaded to 350 ft-lbs.  We recommend torquing these bolts with ARP Moly Lube to a minimum of 350 ft-lbs to ensure clamp loads that will not allow slippage even under the most extreme engine torque.

This is low production part meant for the few chasing every imaginable HP thus the price tag (We aren't making any money on these).  For those interested in having a larger batch made (10+), please reach out for lead time and pricing.