Scott Dixon leads Chevrolet sweep of IndyCar pre-season test

Ganassi's Dixon led a Chevrolet engine and aero kit lockout of the top five places, with Andretti Autosport's Ryan Hunter-Reay the top Honda runner, nearly four tenths of a second back.

"I think both cars are very different," said Dixon. "I don't care what it looks like as long as it's fast.

"It's been a significant change in driveability or how to attack the car with all the downforce.

"We're working with the balance issues, just trying to feel out some of the changes with the aero kit and the loads changing significantly with the corner speeds."

Pagenaud set the pace in the morning session for Penske, which had all four of its cars in the top five at the end of the day, with Will Power ahead of Juan Pablo Montoya and Helio Castroneves.

2012 champion Hunter-Reay described the Honda aero kit, which was outpaced in testing at NOLA Motorsports Park last weekend as well, as "a work in progress".

"This is what testing and development is about," he added. "It's almost like you're starting with a new car.

"You feel when you're in the car that every lap is critical because you're one step closer to the season beginning."

IndyCar is also using this test to trial a new LED display that will show a car's race position, to make events easier to follow for fans at trackside.

The test continues on Tuesday, before the teams switch to private testing at Sebring and NOLA.

The test also marked confirmation of two more driver signings for 2015, with Carlos Huertas signing for a second season with Dale Coyne, and former Auto GP racer Franceso Dracone returning to IndyCar for the first time since 2010 in a four-race deal alongside him.

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