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 John Force Racing drivers are ready to kick off the Western Swing. Here's how the teams are preparing for Sonoma Raceway.
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The NHRA Western Swing kicks off at the Sonoma Nationals. Leah Pruett and Matt Hagan want to start it off strong this weekend.
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Chad and Hunter Green are looking to land in the final round at Sonoma. The father/son duo have found more performance after testing.
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Ron Capps and Maddi Gordon are rolling into Sonoma ready for a big weekend. The teammates are coming off a double up at Norwalk.
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Brian Brooks? sleek new Chevy II sports power from a 480-inch nitrous small-block built for no-time competition.
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Kalitta Motorsports Team Ready For Battle At Denso NHRA Sonoma Nationals
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