Justin Wilson at Houston

HOUSTON -- A record-tying 11th race winner this season is a distinct possibility on a relatively unknown racing circuit.

That much has been gleaned so far through two practice sessions for the Shell and Pennzoil Grand Prix of Houston on the 1.634-mile, 10-turn circuit carved out of the parking lots of Reliant Park.

IZOD IndyCar Series championship contenders Helio Castroneves and Scott Dixon quickly displayed in the first session that their cars will be fast, while Justin Wilson, Will Power and rookie Tristan Vautier significantly lowered lap times in the second 45-minute session.

Wilson, driving the No. 19 Boy Scouts of America car for Dale Coyne Racing, posted the fast lap of 1 minute, 04.4237 seconds on the 18th of his 20 laps. Power, fastest in the first practice (1:06.3983) in the No. 12 Verizon Team Penske car, was .3790 of a second behind Wilson. Vautier was third fastest of the day (1:04.9946) in the No. 55 Angie's List Schmidt Peterson Motorsports car.

“It’s a new circuit and the day was fine. Everyone got a good idea of the track," Power said. "It’s a long weekend with the two races, but hopefully, we can qualify at the front and have a shot at two wins this weekend."

Click it: Combined practice results || Race 1 qualifying groups || Race 2 qualifying groups

Wilson, a seven-time Indy car race winner who is seeking his first victory of the season, is coming off a fourth-place finish on the streets of Baltimore. He has three top-five finishes, including a pair of podiums, in the eight street course races. The Indy car record of 11 different winners was set in the 2000 CART season and matched in '01.

"It’s a tough track and it’s really bumpy, but when the grip comes up, it feels good," Wilson said. "Once the car starts to work around here, it’s a lot  fun, but it’s tough. It’s really physical and you’re bouncing around and you’re trying to land in the right spot and get on the brakes and try not to lose one end or the other."

Dixon, who enters the weekend doubleheader 49 points behind Castroneves, was second fast in the initial practice session and sixth in the second session (1:05.7512). Castroneves followed placing third on the time sheet in the first practice with 11th place (1:05.7512).

Click it: Listen to post-practice news conference

Practice sessions and qualifications for the IZOD IndyCar Series and Firestone Indy Lights were revised because of a surface issue in Turn 1. A temporary chicane to slow the cars was employed until grinding of the racing surface at Turn 1 could take place overnight. That area of Reliant Park is utilized to store the grass field for Reliant Stadium.

"It was a unique challenge the last 96 hours turning the parking lot into a racetrack starting right after the Texas game," said Martyn Thake, director of operations for the promoter. "There have been so many things moving and interlocking at the same time. A facility like this used as much as it is, it was an area we weren't able to explore too closely until we took over the facility. I think the solutions we've come up with will work out fine."

IZOD IndyCar Series qualifying for Race 1, scheduled for Oct. 4, will be held at 11:50 a.m. (ET) Oct. 5. The three rounds of qualifying for road/street circuits, including the Firestone Fast Six, were forfeited for a 30-minute session split into two groups for 12 minutes each of track time. The 90-lap Race 1 with a standing start will proceed as planned at 3:30 p.m. (ET).

Race 2 qualifying will replace the 30-minute warmup at 9:45 a.m. (ET) Oct. 6, followed at 12:30 p.m. (ET) by the second 90-lap race. Both races will be broadcast on NBC Sports Network.

Real-time Timing & Scoring augmented by the IMS Radio Network broadcasts for all on-track sessions is available on www.indycar.com and the INDYCAR 13 app. 

Castroneves knows his championship margin is tentative with three races remaining. Dixon swept the doubleheader in Toronto, the back end of a three-race winning streak in July, to vault from seventh in the standings to second.

Castroneves has recorded 12 consecutive top-10 finishes, including his lone victory at Texas in early June.

“At this point we have to go with the flow. If I have a good car, we’ll go for (the wins)," Castroneves said. "Those people in the attack mode have more to gain, but we’re not going to drive like an old lady and just try to finish the race.

"We have to be rough when we have to be rough and have to be smart. That’s our approach right now, and we have to get what we can out of the car. We have to keep doing what we’ve been doing, which is be consistent and get the most points we can.”

The physical racetrack and lack of practice time doesn't make the task any easier for Dixon, a two-time series champion.

“If we could replicate Toronto, it would make things a lot better," he said. "Looking at trying to do that is not impossible but it’s going to be very tough. As far as street courses go, our car has been pretty good at Baltimore and Toronto.

“Helio has had a consistent year and to be in the lead by this much at this point of the season with only one win is pretty astonishing. If they continue to do that it maybe gives us more opportunities. We’re fighting from behind and it’s a sizable gap, but with 162 points on the table it’s definitely achievable. We probably need a little bad luck on their part. The leader at this point has the advantage. Anything is possible; you have to keep an open mind to start.”