NASCAR cars getting big wheels in 2021

F1 is switching to 18-inch wheels too

Goodyear’s director of race tire sales, Gregg Stucker, confirmed with SiriusXM NASCAR Radio on Thursday that the cars will be switching from 15-inch wheels to 18-inchers in 2021, the same year that the Formula 1 series is scheduled to do the same.

An all-new rules package is scheduled to debut that season and will include a complete redesign of the cars aimed in part at making the vehicles look more like the production models that they represent.

Very few vehicles – and no sports cars — use 15-inch wheels these days, as many consumers have come to prefer the larger designs and ride and handling characteristics provided by the lower profile sidewall tires that go with them. But Stucker said they present particular challenges on an oval racing circuit.

Today's NASCAR wheels

“As that race car goes into these high-banked race tracks, particularly the mile-and-a-halfs, almost all the load is transferred into that right front quarter, and that right front tire absorbs a lot of energy, absorbs a lot of load, and it’s got a very long sidewall in order to do that."

Stucker said the tires will likely be wider and made from new rubber formulations to counteract the change. NASCAR is still developing the 2021 regulations and is considering all factors, including aerodynamics and power, in an effort to improve the competition.