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 FeedsMoney Talks Promotions made headlines recently with the announcement of a new 4-race, $1 million Pro Mod series in 2027.
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FuelTech's new FT470 ECU is packed with new features. The FT470 is FuelTech's first ECU that doesn't come with a built-in display.
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Nitro Chaos racers will race for bigger payouts in 2027. The series will now pay $10,000 to the A-Field winners at every event.
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Numerous IHRA-owned facilities are now up for sale. We've got the tracks that have been listed for auction and when the auctions end.
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Pro Modified veteran Chip King topped a record-setting barrage at St. Louis, breaking the 5.50 barrier with a stunning 5.596-second run.
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