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 FeedsJake Marshall is a Pontiac fan so he had to build a GTO. Marshall's 1966 GTO is totally cool take on the iconic muscle car.
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One of the biggest drag-and-drive events in the country is back. Check out what's going on at Sick Michigan Miles.
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HOT ROD Power Fest is back. EchoPark Speedway will be packed with hot rods, race cars, plus there will be a massive cruise.
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Drag racing is a sport filled with sound, but what if you can't hear? There's a huge section of fans that are deaf and could enjoy the sport.
Small Tire Pro Stock racer David Theisen had his heart set on earning an NHRA Speed For All Wally in Indy, and he worked hard to pull it off.
Recent Technical Articles
Maple Grove Raceway Closes, Suspends Racing Schedule Amid Restructuring
Maple Grove Raceway announced a temporary closure and pause on racing operations. The track is working on a restructuring plan.
NewsSource Yesterday, 01:20 PMMore...