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 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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The 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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The Official Legacy Nitro Funny Car Series 2026 Schedule
The official Legacy Nitro Funny Car Series 2026 Schedule brings eleven massive NHRA events. Prepare for deafening nostalgic racing action.
NewsSource Yesterday, 11:18 PM