Well I came up with the The number of turns head thread Test.
Basically there is a seat in the head for the wider portion of the plugs just above the threads to stop on. This seat, notch, ledge, whatever... read more

Mustang FeedsYou never know what you'll need during a drag-and-drive. We take a look at what goes into building and stocking a drag-and-drive trailer.
Tony Stewart Racing is ready for the Potomac Nationals. Leah Pruett and Matt Hagan are looking for big performances at MDIR.
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Chad Green is having a career-best season. Green is looking to pick up his third win in 2026 at the NHRA Potomac Nationals.
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The Ronnie Buff Memorial has everything a good drag race needs. This grassroots event shined even when Mother Nature had other plans.
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The IHRA is moving its Triple Crown Finale to Maple Grove. Racers will have the chance to run the final two events at the historic facility.
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