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 Right Trailers Outlaw Street Series officially debuts at zMAX Dragway. This crossover brings television racing icons to the NHRA stage.
Mark Viso's 1969 Chevelle is a dream project car that's stood the test of time. The classic Chevy is powered by one nasty big block.
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Ryan Rudrick has grown up around racing. Rudrick now pilots his family's 1970 Duster in NHRA's Stock class at events across the country.
Nitro engines need a whole lot of fuel to make power. On this episode of Tech Inspection we learn about these pumps and how they work.
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Veteran racer Mark Pawuk takes the wheel of the new Dodge Charger Drag Pak. He aims to secure a third consecutive title this racing season.
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