By Bruce Martin SportsTicker Contributing Editor

INDIANAPOLIS (Ticker) -- Tony Kanaan said don't get worked up over the speed he posted in practice Thursday. That's because Kanaan, a rookie at the Indianapolis Motor Speedway, said he got a huge "tow" from fellow CART driver Jimmy Vasser.

Kanaan nearly ran the fastest speed of the opening week of practice when he whipped off a lap at 229.503 miles per hour in a G Force/Chevrolet. It was in the backup car for his teammate at Mo Nunn Racing, Felipe Giaffone of the Indy Racing League.

"I have to thank Felipe, actually," Kanaan said. "He gave me his backup car yesterday, so that was his car. I think it was working better than mine. It feels good to be on the top of it, but it's not a true lap. I got a very good tow from Jimmy Vasser. I need to thank him because it was his tow for the whole lap. That was a hell of a tow.

"I'm just working on my qualifying setup right now and if we have a good, constant four laps, that's all we need. We need to work on getting the pole, but we are going to be good. I'm aiming on a top-10 start and we have a very good race car. It's my first week here so I'm learning a lot. Let's see what we can do Friday and Saturday."

Kenny Brack, the 1998 Indy Racing League champion and 1999 Indianapolis 500 winner who is now in CART, was second-fastest Thursday with a lap at 229.025 mph in a G Force/Chevrolet.

"I said on Wednesday that the car is coming around, and it did today," Brack said. "It was good to post a speed like today. It's good for the confidence of the team and for myself. We have a car that should be pretty good for qualifying, but we'll have to wait and see how things pan out on Saturday."

Defending Indy 500 champion Helio Castroneves of the IRL was third at 228.736 mph in a Dallara/Chevrolet.

"Today, we made very good progress, the track is getting better and better and the cars are getting faster," Castroneves said. "Once again, we did our quick speed on our own, which is very important as we prepare for qualifying. The weather is supposed to be good tomorrow and I think we're going to see everyone's true speeds as we get in our final preparations for Pole Day."

IRL driver Jeff Ward was fourth in a G Force/Chevrolet at 228.571 mph followed by CART's Bruno Junqueira's 228.519 mph in a G Force/Chevrolet.

Brack, Ward and Junqueira all drive for Chip Ganassi Racing.

Laurent Redon continues to have the fastest speed so far in practice after running a lap at 229.808 miles per hour in a Dallara/Infiniti on Tuesday.

Mark Dismore crashed in the final 30 minutes of practice when his car spun in the first turn and crashed backwards in the Steel and Foam Energy Reduction (SAFER) wall. Dismore was transported by ambulance to Methodist Hospital, where he is being treated for a concussion.

According to IRL director of medical affairs Dr. Henry Bock, Dismore will be re-evaluated Monday and will not be cleared to drive for this weekend's qualifications.

For the fourth straight day, practice was delayed by rain. Once the track cleared, 40 cars turned 1,446 laps in the session as Saturday's Pole Day looms.

Kanaan, who is used to the car/engine configuration in CART, admitted that the IRL car feels foreign to him.

"It's a different car with a lot more downforce with a completely different setup," said the Brazilian. "I'm still learning and getting a lot of help from Felipe. I have to thank the guy because he's a great teammate and is really working hard to help me out. That is what makes a team win. We're working together until race day and when the flag drops, we'll race."

Kanaan admits he is more comfortable with the CART car, but said those racers would have too much horsepower for the 2 1/2-mile Indianapolis Motor Speedway.

"It's definitely a lot different than what I'm used to, but we have a whole month to get ready for the race," Kanaan said. "I wasn't comfortable at all until today to run in traffic. I didn't have any confidence in my car. I didn't have any confidence in myself. It's a new place for me, so today I felt much better.

"That's why it's Indianapolis because it's a different oval. Nobody has the same layout. The way the layout of this track is, is the beauty of this place."