When putting tires on a personal vehicle it’s always recommended to tighten the lug nuts in a star or criss-cross pattern, yet when you see pit crews for nascar they just go around one by one very quickly in a circle, why can they get away with doing it that way even though they’re driving much faster so things like a loose lug nut or vibration should be a pretty big deal, but it’s recommended that I always do a star or crisscross pattern?
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The center hub of the old Nascar wheels were nearly the same size as the center of the wheel. This serves to align the wheel on the hub. When you tighten in a star pattern, it does two things, helps correctly align the wheel and second, applies a consistent and even torque to the lug nuts across the mating surface between the wheel and rotor.
In the case of Nascar, they use high torque high speed impacts. These will easily apply 100lbs+ of torque to the lug. Most street cars lugs would strip or break when applying the same amount of torque which is why lugs are both very high quality and commonly replaced. So because the lug nuts are over torqued for their need and the wheel is already aligned and centered, it doesn’t matter if you go in a star pattern. Going in a circle vs a star saves time and making up time on pit road can significantly impact your finishing position.
That being said, at times the wheel would hang and not fully seat when the first lug is torqued. This would often result in one or more lug nuts remaining lose. It’s up to the tire changer to detect this and hit the lug again before the car leaves the pits. It’s a compromise and why Nascar teams train. When changing tires outside pit road, we would still use a star pattern and a torque wrench like you would typically do on a road vehicle.
Also, lugs don’t strip often as some would assume. Unlike a street car, the lugs used have about a two inch threadless section at the end that the lug nuts align to before they engage the treads.
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