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 NHRA has unveiled the 20-race, 2027 Mission Foods Drag Racing Series schedule, featuring a return to the traditional West coast openers.
Joel Grannas' new "Peeled" Mustang is one bad ride. The 2JZ-powered Ford reset the H-pattern world record with a 6.490 pass.
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The rumors of Darana Motorsports Holdings tracks closing continue to swirl. We spoke to management at several tracks and got the truth.
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Santa Pod Raceway is ready to put on a huge show. The track will host the FIA/FIM European finals and much more.
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Ida Zetterstrom will be making her next NHRA start at the U.S. Nationals. Zetterstrom will be driving the Bandero Tequila-backed dragster.
Recent Technical Articles
Jack Beckman To Race John Force?s Iconic 1996 Funny Car Scheme At U.S. Nationals
Jack Beckman will be running a legendary John Force paint scheme at the U.S. Nationals. This scheme honors Force's 1996 championship season.
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