This, however, was as close as we could get to testing the same tire in every size. We used the stock steel wheels for the 15-inch test and ... but we measured a 10-percent drop in fuel economy ...

For most vehicles, a wheel and tire upgrade is categorized ... Most of us understand how wheel sizes work: a 17x10-inch wheel is a 17-inch-diameter wheel with a 10-inch-wide width.

Fuel consumption might increase by 10% on a car that was fitted with 15-inch rims from the factory and then goes all the way to 19-inch wheels and tires. The 0-62 MPH (0-100 km/h) time also drops ...

For now, the tire design is just a concept limited to a 10-inch outer diameter ... that combines intelligent steering, braking, in-wheel electric drive and suspension hardware.