Thursday practice: Toyota leads way

Junqueira was the only driver to circulate the 1.549-mile oval in less than 26 seconds. His 25.983-second lap worked out to an average speed of 214.479 mph.

"My car was fast right out of the box and I could do anything I wanted," said the Brazilian. "We'll have to see how it holds up tomorrow when everyone bolts in their best engines tonight. But I'm happy with the power I'm getting from Toyota."

Ford's Patrick Carpentier ran second ahead of Honda's Dario Franchitti in third.

"All three engines are extremely close, but it changes every race and will continue that way throughout the season," Carpentier stated. "Hopefully, Ford will stay on top like it has for the last four years."

Franchitti stuck with the tried-and-true Reynard chassis while his Team Green team-mates Paul Tracy and Michael Andretti ran Lolas for the first time.

"The car was very strong, like last year," Franchitti said. "I think Lola has more scope for development over the course of the season since they're still in business, but we'll have to see where it goes from here."

Tracy was second fastest in the morning but his afternoon was cut short by a wheel bearing failure in his Lola-Honda.

"The Lola is really good," Tracy said. "It suits me a lot better than the Reynard - I can drive it the way I want to rather than adapting my style to the car. It's good that we had the problem today rather than on race day."

Cristiano da Matta ran fourth to head Tony Kanaan and Alex Tagliani as the three engine manufacturers evenly split the first nine places. Those nine drivers were covered by less than 0.3 second. Thursday's activities at Motegi were held in cool and overcast conditions.

There is a chance for rain Friday, which would mean the grid would be set based on practice times. "We concentrated on race set-up for most of the day, but we bolted on a new set of tyres to get a good lap in the bank in case qualifying gets rained out," added Franchitti.