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 FeedsQualifying kicked off Friday at the U.S. Nationals. Langdon, Beckman, Stanfield, and Smith took the provisional No. 1 qualifying spots.
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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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