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 FeedsReigning Top Fuel champion Doug Kalitta clinched the $150,000 regular season championship and the Countdown top seed at Indianapolis.
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If you're looking to customize your ride RC Components has a wheel for you. The Kolor Pop wheels feature bold colors and great designs.
Matt Hagan claimed the Funny Car regular season championship. Hagan will roll into the Countdown as the points leader.
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Scott Libersher upset Jonathan Allegrucci to win Factory Stock Showdown at the U.S. Nationals. It's his first victory of the season.
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Lucas Oil has added another 25 years to its NHRA sponsorship. The company will continue to sponsor the LODRS and much more.
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Recent Technical Articles
Nitro, Tire Smoke, And History: The U.S. Nationals In Pictures
The U.S. Nationals is the kind of event that just has to be experienced. Here's a look at what The Big Go in pictures.
NewsSource Yesterday, 12:43 PMMore...