Teams commence Indianapolis test

Two of them employed the new 3.5-liter Honda engine and 100 percent fuel-grade ethanol that will be used during the 2007 IRL IndyCar Series season.

Tony Kanaan and Jeff Simmons drove the 3.5s burning the ethanol fuel, a renewable, grain-based fuel derived primarily from corn. Drivers reported few problems from the initial test, the first at the Speedway for 100 percent ethanol.

The IRL used a 90 percent methanol and 10 percent ethanol blend last season.

"Aside from a little bit of a smell difference, there isn't much difference," Simmons said. "It's got a broader power band, which is immediately noticeable. You can let it drop down on the revs, and it will still pull its way back up. Last year, it wouldn't do that. We can run different gears and basically run the same times."

While Simmons and Kanaan tested the new engine/fuel combination, two other drivers - 2005 Indy 500 winner Dan Wheldon and two-time 500 winner Helio Castroneves -- tested with the 3.0 engine and 90/10 fuel blend. No incidents were reported, and speeds were not made public.

The use of ethanol in 2007 will mark the first time a major-league motorsports series has used grain-based fuel. Honda engineers have deemed the 3.5 necessary for use with the fuel, largely to ensure reliability. Ethanol burns hotter than methanol, but is also more efficient.

"In terms of driving an engine with ethanol, nothing really stands out as far as differences," Simmons said. "The broader power band is what I really noticed. It seems to be stronger and pulls a little better.

"It makes better mileage, so we've been seeing the different numbers on that. Honda has been working on software things like the pit limiter and shift cuts, but overall it went very well."

The primary reason for the test, of course, was tires, and the four drivers went through various compounds through the course of several hours on track.

"It's (Firestone's) way to keep up with safety and the development of the race cars," Wheldon said. "The engineers and race teams these days are moving things very fast, and it's important because it is such a competitive series."

The test continues Tuesday with the same four teams.