NASCAR is constantly trying to improve car safety and help team owners trim the high price of operating a racing team.

For the 2021 racing season, NASCAR will introduce a “Next Generation” car.

Among those changes is a new wheel design that will eliminate one of the biggest causes of team penalties – lug nuts. The new wheel will go from 15 inches to 18 inches and from the five lug nuts to only one – a center-locking system.

Speaking on the new design, NASCAR Senior Vice President of Innovation and Racing Development said, “for us we felt like from a standpoint of the wheel is that we wanted to get to an 18-inch wheel, an aluminum wheel. Once you get to an 18-inch aluminum wheel, the next step for us is to make sure that from a durability standpoint under racing conditions is that it will accept the durability that we need to finish races and then also finish multiple races. To do that, the single nut was our only option.”

Probst noted that the new wheel and lug nut design is not expected to alter the current format for pit stops and crews; saying, “I think from a fan standpoint, the choreography of the pit stop will look unchanged. I think that a lot of times when we say single lug nut, people fear that it’s an open-wheel style pit stop where people will be on their knees waiting for the car to come in. We don’t intend to change anything with respect to how the pit-stop flow is executed.”

Probst added, “t here will still be guys coming off the wall, there will still be a premium for that athlete to come off the wall, get to the right side of the car, make that tire change, get over to the left side of the car and make the tire change. From the look and feel of the pit stop, we don’t see any significant changes.”

Currently each team is allowed five pit crew members over the wall to work on the cars during a pit stop.

But the new design will also require more torque to secure which means that pit stop times will not change much…if at all.

Probst continued, “the steel wheel is more forgiving and can handle loose wheels a little bit better. When we get to the aluminum wheel, we did some durability studies and if you leave lug nuts loose on an aluminum wheel, you reduce the durability of the wheel by around 30%. It’s more of, the aluminum wheel has less tolerance to loose lug nuts, so when we have one, there really is only one thing to concentrate on, and that is to get that lug nut tight. Then everything else from a durability standpoint is fine.”

Teams routinely prepare tires for changing during pit stops by gluing the lug nuts onto the tires prior to each race. With the new one lug nut system, that process will no longer be required; which will save a little time during pre-race preparations.

Probst explained, “one of the things when you look at the single nut, it actually is retained in the socket, so they’ll actually use the same single wheel nut for the entire race and likely multiple races. They’ll use the same lug the entire time, so the concept of gluing lug nuts to tires goes away, which creates some efficiencies for us. There’s times when we have to open up the garage or pit road early on race day for no other reason than for the race teams to glue up 11 sets of tires. They can just use the wheels as they are without being glued.”

NASCAR is in the process of testing the new car design now at various tracks on the NASCAR circuit.