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 FeedsNitro teams bring an incredible amount of gear to the track. We take a look at what you'll find inside one of John Force Racing's trailers.
Matt Hagan is working towards picking up another NHRA Funny Car championship. Leah Pruett has a shot to make waves in Top Fuel.
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Chad and Hunter Green are ready for their home national event. The father and son Funny Car duo are chasing the cowboy hat in Dallas.
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Fuel Altered CHAOS is coming to Tucson. 30 rowdy Fuel Altereds are ready to dance in the desert to see who can claim the crown.
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Doug Herbert's B.R.A.K.E.S. program brought racing stars together for the Race 2 Save Lives event. Check out who made laps at the race here.
Recent Technical Articles
NHRA Outlaw Street 3.66 ET Limit Explained After Texas FallNationals Controversy
Contrary to what social media has said the NHRA didn't put an index cap on Outlaw Street. Here's the truth behind the 3.66 number.
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