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 FeedsVeteran racer Mark Pawuk takes the wheel of the new Dodge Charger Drag Pak. He aims to secure a third consecutive title this racing season.
The Gatornationals roared to life at Gainesville Raceway. Check out this photo coverage by Mark Riker from the 2026 NHRA season opener.
Batteries can be damaged by excessive amounts of heat. DEI created the Cell Saver to protect your battery from heat exposure so it will last.
Drag Race Bracket Bonanza empowers fans with The Major Moments Brackets. Vote for the greatest milestones in historic NHRA drag racing.
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Trying to save weight and add strength to a race car can be a struggle. Strange Engineering has a solution with its aluminum center sections.
Recent Technical Articles
Inside A Nitro Fuel Pump: How Top Fuel and Funny Car Engines Get Fed
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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