Clever fastening technology keeps top-fuel dragsters on track

Jan. 26, 2006
An innovative fastener-locking system with a new wrenching feature is preventing failures and costly downtime in top-fuel dragsters.

Tony Schumacher's top-fuel dragster is a good test of Stage 8 locking fasteners.


The idea for the fastener arose when engineers at Stage 8 Locking Fasteners Inc., San Rafael, Calif., asked, "If a wrench is good for tightening bolts, couldn't a retainer that acts like a wrench lock a bolt tight?" Today, many industries use the retainer-based locking fastener for critical applications.

At the drag strip, fasteners hold the hub bushings on the rear-end assembly of 7,000-hp top-fuelers. "You could wreck a $20,000 rear end simply because four screws came loose. And somebody could get hurt," says Jeff Capek of Strange Engineering, a Morton Grove, Ill., manufacturer of racing equipment. Capek tested a prototype fastener from Stage 8 and has had no problems in field trials.

The fastener virtually eliminates critical joint failures. The GrooveLok fastener acts like a wrench locked onto a bolt head. The locking retainer can be braced against a frame, casting, or other protrusion, thereby locking the bolt or nut in place. Bridge retainers can fit over two or three bolts, locking them together, or a retainer can be bent over an edge or frame.

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