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 first IHRA Triple Crown race took a hit from Mother Nature. The Maple Grove event has been postponed due to heavy rain.
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Shayne Johnson's 1970 Nova is a work of art. This 2,700 horsepower race car just happens to have the looks of a show car.
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The IHRA is going to be looking for a new President. Leah Martin announced that she's parted ways with the sanctioning body on Monday.
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Jonathan Allegrucci picked up another Factory Stock Showdown win. Allegrucci has dominated the class this season with two wins.
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Derek Menholt is the first two-time NHRA Pro Mod winner this season. Menholt is now the NHRA Pro Mod points leader heading into Bristol.
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Nick Hastings Sweeps $15K Races, Randy McFarland Banks $50,000 at Autoland Door Car C
Big money was on the line at Byron Dragway. Here are the winners that brought home the cash from the Autoland Door Car Challenge.
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