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 Shakedown At M'Town put on a great show. Here's all the highlights from this Pro Mod and radial racing event.
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The NHRA's first visit to Maryland International Raceway was epic. Here's who won at the first NHRA Potomac Nationals.
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The NHRA Mission Food Series kicked off qualifying Friday at the Potomac Nationals. Here's who sitting number one in each class.
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Eric Russell wanted to build something that wasn't a Mustang for his project car. Russell's 1985 Thunderbird is a supercharged beast.
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You never know what you'll need during a drag-and-drive. We take a look at what goes into building and stocking a drag-and-drive trailer.
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Mustang Week Charlotte Turns Up The Heat With Four Classes Of Drag Racing Action
Mustang Week Charlotte has some great drag racing classes on tap. Here's how you can race your Ford at zMax during the event.
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