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 FeedsSanta 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.
ATI now offers a Pressure Dump Kit for powerglide transmissions. This kit is designed to make torque converter manipulation easier.
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Del Worsham and Jake Slater debut a new blown-nitro Top Alcohol Funny Car combination at Brainerd, setting the national record at 291 mph.
The NHRA Brainerd Nationals had huge points implications for all pro categories. Here's a recap of who won at Brainerd this weekend.
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Recent Technical Articles
Darana Motorsports Holdings-Owned Tracks Push Forward As Independent Businesses Amid
The rumors of Darana Motorsports Holdings tracks closing continue to swirl. We spoke to management at several tracks and got the truth.
NewsSource Today, 10:48 AMMore...