Words and photos by Bill Holland                       

ABOVE: Doug Herbert’s engine goes ballistic at the 1999 NHRA World Finals. (Jeff Burk photo)

Not all engines expire as spectacularly as a supercharged nitro-burner in the lights. For most racers, a catastrophic engine failure is more sedate than a giant fireball, but both have the same consequences —a massive engine rebuild is required. And in many cases, the problem can be traced to fastener failure.

For some input on the matter we turned to the folks at Automotive Racing Products, Inc., better known by their initials, ARP. The firm was started over 40 years ago by Gary Holzapfel and now headed by his son, Mike. The company has one of the nation’s most comprehensive in-house R&D facilities dedicated to fasteners, and has a plethora of equipment that rivals the OEMs.

Sophisticated computer-controlled devices are used to measure the tensile strength of fasteners, number of cycles before failure, and amount of preload applied. Other devices are used to analyze threads, material composition, surface hardness and many other parameters. ARP’s R&D team includes highly credentialed experts Kenneth Foster, PhD and Russell Sherman, PE, as well as a number of skilled technicians with many years experience dealing with engine builders and race teams in virtually every form of motorsports from Formula 1, NASCAR, NHRA and dozens more. These guys know fasteners!