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 FeedsARP is adding bonus award money at California Hot Reunion. The company is kicking in an extra $12,500 to the long standing event.
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It was a big day for the Pawuk family at Dallas. Both Mark and Kyle scored national event wins at the 2026 NHRA Texas Fallnationals.
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The NHRA Texas FallNationals was one of the best events of the 2026 season. Brown, Todd, Glenn, and Smith all scored huge Countdown wins.
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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Nitro 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.
Recent Technical Articles
A 6.434 And The Quickest Field Ever: Pro Stock Makes History In Texas
It was a record-breaking weekend for Pro Stock. Dallas Glenn reset the national record and led the quickest Pro Stock field ever.
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