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 FeedsThe 2026 NHRA Pro Mod season kicked off at the Gatornationals. Derek Menholt was able to bring home his first NHRA Pro Mod win of the season.
The Factory Stock Showdown season opened at the Gatornationals. Ricky Hord ran through a tough field to pick up the win.
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The turbocharged Coyote 10 Chevy C10 chases a 4-second eighth-mile with over 1,500 horsepower using some minor upgrades.
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Fasteners play a critical role in high-performance engines. Here's a look at what makes a high quality fastener work.
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Austin Prock failed to qualify in his debut with Bob Tasca's team at the NHRA Gatornationals after a shocking offseason move.
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Hart, Green, Hartford, And Gadson Win At Amalie Motor Oil NHRA Gatornationals
The NHRA kicked off its 75th season at Gainesville Raceway at it was a great event. Here's a recap of the 2026 Gatornationals.
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