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 Factory Stock Showdown field at Indy is stacked with great racers. Jonathan Allegrucci is trying to seal the points title at the Big Go.
Frank Hawley's Drag Racing School has trained thousands of racers. Hawley is now back in the ownership seat of the school.
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Selecting the right crank and rods for your boosted engine is critical. We explore what you need to know to pick the right parts.
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Chad and Hunter Green will race both race at the U.S. Nationals. Chad chasing championship points and Hunter seeking his first win.
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At the 1989 U.S. Nationals, a frustrated Ed "The Ace" McCullough drove his Funny Car all the way back to the pits after a tire-smoking loss.
NewsSource 09-03-26, 06:40 AM
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Spencer Hyde Joins Star-Studded Funny Car Callout Field At The Big Go
Spencer Hyde is in the 2026 PlayNHRA All-Star Funny Car Callout at the U.S. Nationals. He?ll race a star-studded field for an $80,000 prize.
NewsSource Yesterday, 06:50 AM