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 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.
More...
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.
The official Legacy Nitro Funny Car Series 2026 Schedule brings eleven massive NHRA events. Prepare for deafening nostalgic racing action.
Recent Technical Articles
Mark Pawuk Debuts The All New Charger Drag Pak Car
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.
NewsSource Today, 09:30 AM