Indycar is looking to electrify the series by switching to a hybrid formula in 2022.
The series announced the move on Monday. It originally planned to update its engine rules for 2021, but said the new development would delay that by one year.
The rules call for a single-source hybrid unit comprised of a multi-phase motor, inverter and electric storage device for energy recovered under braking. It will double as a starter motor for the cars, eliminating the need for handheld units and allowing drivers to restart stalled vehicles on the track.
Engine suppliers Honda and Chevrolet will pair the unit to their own internal combustion engines, and the series is hoping the new formula will attract a third manufacturer for 2022.
Along with increased efficiency and a green image, Indycar expects the hybrid powertrains to deliver a maximum of 900 hp when drivers engage push-to-pass, up from around 750 hp today.
A new spec chassis is also in development and set to be launched in 2022, and the new regulations will be in effect through 2027.