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 FeedsHeads-up racers Chris and Jeff Harrington are stepping away from their familiar combination in order to fly even faster in their Mustang.
Street Car Braggin Rights is the ultimate grassroots racing event. Check out this gallery of action from SCBR at Rockingham Dragway.
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Elite Motorsports rolls into zMax with a positive head of steam. Here are the big Elite storylines heading into the 4-Wide 'Nats.
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Brett LaSala's Coyote combination just got hit hard with rule changes. Here are the changes in the LDR rules for the Coyote combination.
Buddy Hull is ready to take on a new racing challenge. Hull will be stepping behind the wheel of a radial tire Mustang.
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Recent Technical Articles
Matt Hagan, Leah Pruett Lead Tony Stewart Racing Charge At zMAX Dragway
Tony Stewart Racing's Matt Hagan and Leah Pruett are ready for the 4-Wide Nats. Here's what they're bringing to zMax Dragway
NewsSource Yesterday, 07:00 AMMore...