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

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Vote For The Final Team In The Horsepower Wars $10K Drag Shootout Presented By Summit
It's time to pick the final team for the Horsepower Wars $10K Drag Shootout. Here's how you can vote for your favorite team.
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