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 FeedsJonathan 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.
Veteran nostalgia racer Kyle Hough suffered severe leg injuries in a violent crash aboard at Tucson Dragway?s Fuel Altered Chaos on Saturday.
The NHRA made a stop at Route 66 Raceway for another big event. Here's who won at the Route 66 NHRA Nationals.
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The historic tenth season of the MWDRS started with a bang in Tulsa. Shawn Ellington claimed the Pro Mod victory over rookie Ryan Martin.
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IHRA President Leah Martin Let Go From Organization
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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