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 FeedsOnce again the NHRA Pro Mod championship came down to the final round in Vegas. Justin Bond beat Mike Stavrinos to win the title.
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The Las Vegas Nationals turned up the heat on the chase for NHRA world championships. Here's a recap of all the final round action from Vegas.
ARP has developed a kit that deals with damaged threads on LS engine blocks. ARP's new stud kit uses oversized threads to save blocks.
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Chad Green is ready to grab his third win of the 2026 NHRA season. Chad and his son Hunter both will be racing at The Strip this weekend.
James Foreman's 1981 Z28 Camaro can throw down some big numbers on a small tire. The car has run deep in the 4.30s on a 8.5-inch tire.
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Recent Technical Articles
History Made: First All-Three-Second Funny Car Field In NHRA History
NHRA Funny Car history was made at Las Vegas. For the first time ever the entire field of Funny Cars cracked the three-second barrier.
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