Dixon admits 'we're not comfortable with Dallara.'

Scott Dixon switched back to his Panoz chassis for the second official day of practice at Indianapolis on Wednesday and instantly headed towards the top of the speed charts as his Indy 500 chassis dilemma deepened.

After nominating a Dallara as his primary chassis despite completing less than one racing lap with it in Japan, Dixon spent Wednesday in the Panoz chassis that he started the year with, but which was only nominated as his back-up machine for Indy.

Although nearly all of the 28 drivers who turned a lap of the 2.5-mile quad oval on Wednesday posted their fastest times of the month so far, Dixon's leap from 19th overall on Tuesday to 3rd fastest on Wednesday gives the 2003 Indycar Series champion plenty to think about when choosing which chassis to stick with for the remainder of the month.

Dixon's Target Chip Ganassi Racing teammates Darren Manning and Ryan Briscoe will both be running the Panoz chassis at Indianapolis and finished the day 16th and 20th fastest respectively.

"We've worked for years with the Panoz and that is what we are most familiar with," said the New Zealander. "It was easier today simply because of habit really. It is in no way a slight on the Dallara chassis. We just aren't comfortable enough with it right now."

After failing to top 220mph on Tuesday, Dixon rocketed up the speed chart on day two, eventually recording a best lap of 226.816mph. Although he later admitted that he had the benefit of a tow on his quickest lap, practice leaders Tony Kanaan and Danica Patrick also admitted to catching a significant draft on what turned out to be their fastest laps as well.

"We worked on the general feel of the Target car today with set up and downforce, then trimmed it out a bit near the end there," he continued. "I went out on new tyres and got a good tow but we've got a pretty good feel where we want to go in terms of handling for both qualifying and the race."