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 FeedsMatt Hagan and Leah Pruett are ready for Route 66 Raceway. The TSR team is locked in for a big weekend at the Route 66 NHRA 'Nats
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If you're going to push a Gen III HEMI to its limits you need a strong engine block. Here's a look at Callies' Hellephant HEMI block.
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Racing season rolls on and ProCharger racers have accumulated more wins. Here are the ProCharger racers who won big in April.
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Elite Motorsports brings its full stable of racers to Route 66 Raceway. Tony Stewart is ready to bring home another Chicago win.
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Chris King is ready to make his 2026 NHRA debut. The Chicago native is excited to race at Route 66 Raceway in front of his friends and family.
Recent Technical Articles
Route 66 Raceway Could Be Turning Point For Chad Green Motorsports
Blake Alexander returns to NHRA Funny Car action this weekend. Chad Green is ready to get back to the winner's circle at Joliet.
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