Four-time Indycar champion Scott Dixon is predicting the new 2018-aero kit used in the category will be the biggest change the sport has seen in five years.
Dixon, who finished third in this year's championship, recently tested the unified aero kit that will be used on both Chevrolet and Honda cars next year.
"We've been going in a direction for the last five to six years of adding downforce over and over, and now this is a pretty massive step in opposite direction, especially on road courses," the Chip Ganassi driver told Motorsport.com.
"Even in some of the recent testing, it's changed the dynamic more than I've seen in the last five years.
"From what we've seen so far, it's definitely different to drive."
Dixon is predicting a radical change on road or street courses.
"Speedways and superspeedways aren't going to change too much, but short oval, road and street courses are drastically different," he said.
The 2018 Indycar championship starts on the streets of St Petersburg, Florida in March.