INDIANAPOLIS -- INDYCAR, the sanctioning body of the IZOD IndyCar Series, has modified the activation delay to the overtake assist for GoPro Indy Grand Prix of Sonoma at the raceway in Sonoma, trimming the interval from 5 to 3.5 seconds.

A total of 90 seconds will be afforded drivers, with a maximum of 15 seconds per activation. There's no recharge time between activations.

"All parameters of the Push-to Pass system can be tailored to fit any circuit that play host to IZOD IndyCar Series races," said INDYCAR Director of Engine Development Trevor Knowles. "Sonoma has shorter straightaways than what we had at Mid-Ohio, so we've adjusted the parameters of Push-to-Pass to fit this particular circuit. But the principles for use that were in place for Mid-Ohio have remained the same for Sonoma."

The overtake assist feature, introduced to the series in 2009, allows a driver to add turbocharger boost and additional RPMs with the press of a button on the steering wheel. When the system is engaged, the turbocharger boost increases to 161 kPa with an additional 200 RPMs on the 2.2-liter V6 engines supplied by Chevrolet, Honda and Lotus.

The system has been utilized at Toronto and Edmonton with the activation delay introduced at Mid-Ohio. Teams had the opportunity to test the system with the delay during the private test day at Sonoma on Aug. 17.