INDIANAPOLIS (AP) -- IndyCar is bringing back the push-to-pass feature for the remaining five road and street course events this season, starting next week at Toronto.

The option, introduced in 2009 to increase passing in the series, gives drivers an added turbocharger boost and additional RPM with the push of a button located in the steering wheel.

The boost is only given for a pre-determined amount of time set by IndyCar at each venue. IndyCar will also decide the total amount of time the additional boost can be used during a race.

Push-to-pass will not engage until a certain throttle position is reached, and it will disengage if the driver lifts or presses the button again.

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