IndyCar Series officials have announced that a push to pass system will be introduced from this weekend's race at Kentucky.

The system will come in alongside a series of aerodynamic changes in an effort to improve racing, and will be available through the remaining events on the 2009 schedule.

Drivers will be able to call upon a power boost of between 5-20bhp for a limited time, which change on a race-by-race basis. The amount of extra power available will depend on whether or not drivers are conserving fuel when they elect to use the system.

In Kentucky, drivers will be able to call on the system 20 times for twelve seconds at a time.

"If you're on the rich side, you get 5 horsepower because the engine already is producing close to its maximum, where you can get up to 20 horsepower if you're running lean," Indy Racing League senior technical director Les Mactaggart said. "It's to provide the driver, if they're already making a passing manoeuvre, an additional tool to complete the pass. It provides the teams with options which they have to choose how they're going to run, so it brings more strategy from a team aspect.

"Because of the architecture of the engine, you can't have the 100 horsepower that Champ Car had because you could just increase your boost levels on a turbocharged engine and that's how you get the extra power.

"When you're already producing 100 per cent power with a normally aspirated engine, there isn't anything else other than spark advance to get more horsepower."

Honda Performance Development race team manager Roger Griffiths said he was hopeful that the new system would lead to an increase in overtaking through the remainder of the year.

"We hope that the new Honda button feature will add a little spice to the racing," he said. "It gives the driver/team an additional tool to use during the course of the race that we believe will promote some additional overtaking with the added complexity in that the feature won't be available until the actual race so teams will have to experiment on the fly."