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 first IHRA Triple Crown event is shaping up to be huge. Ron Capps and Maddie Gordon will be at the Maple Grove race.
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Nitro Funny Car clutch tuning is super complex. In this episode of Tech Inspection we learn about clutch tuning from Tim Fabrisi.
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IHRA acquires Empire Dragway. It has announced upgrades, expanded events, and a long-term investment in Northeast drag racing facilities.
Sean Bellemeur added another big line to his racing resume at zMax. Bellemeur recorded his 50th NHRA national event win.
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Factory Stock made its return to the NHRA this weekend. Jonathan Allegrucci brought home the NHRA 4-Wide Nationals win.
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Recent Technical Articles
Gas vs. Electric? Ford?s Six-Second Cobra Jet 2200 Might Change Your Mind
The Cobra Jet 2200 isn't you're standard EV. This Mustang reset the electric vehicle drag racing record with a 6.78 at 222 mph.
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