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 Mid-West Drag Racing Series returned to US 131 Motorsports Park with a big field of Pro Mods. Here's a recap of the event.
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Full Floater rearends are designed for extreme racing applications. Here's a look at the design of these rearends and what makes them strong.
Known for his fast heads-up cars, Rick Bailey is adding a 1955 Chevrolet built for the fast-growing 5.30 index class.
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Pistons In The Pines takes racers on an epic adventure through the state of Maine. Check out who won at this drag-and-drive event here.
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Shane Gray is making his return to NHRA racing in 2027. Gray will pilot a Pro Mod for Elite Motorsports next season.
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Recent Technical Articles
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Summit Motorsports Park's Night Under Fire put on one heck of a show. Check out our recap of this epic event and massive photo gallery.
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