Mitsubishi 4G63 M11 (Custom Age 625+) - ARP Head Stud Kit

They say that to be successful you must identify a need and satisfy it. Back the early 1970s, racing enthusiast Gary Holzapfel saw that many of his friends’ broken engines were caused by fastener failure.

At the time, there were no commercially available studs and bolts up to the challenge. So Holzapfel called upon his many years of fastener making experience for a leading aerospace subcontractor and founded ARP (Automotive Racing Products).

In the ensuing years, the firm has grown from what was literally a backyard garage workshop into a highly diversified manufacturer with seven operational entities in Southern California with a combined area in excess of 200,000 square feet. These include forging, heat-treating, machining, quality control finishing and packaging/warehousing facilities in Santa Paula and Ventura, California.

There is even a unique racing-themed restaurant at the main Santa Paula facility - called “ Hozy’s Grill” - which is open to the public.

Today, ARP’s product line contains thousands of part numbers, and has expanded to include virtually every fastener found in an engine and driveline and throughout the suspension and frame. These range from quality high performance OEM replacement parts to exotic specialty hardware for Formula 1, IndyCar, NASCAR and NHRA drag racing and marine applications.