DETROIT (AP) - Helio Castroneves thinks he might be hitting his prime - now that he's celebrated his 39th birthday.
Castroneves capped a dominant weekend for Penske Racing in Detroit with a cruise down a bumpy street on Belle Isle, where he won the first of his 29 open-wheel races in 2000.
About an hour after his second win of the year, a 1.6836-second victory over Penske Racing teammate Will Power at the Detroit Grand Prix, Castroneves already was thinking about racing at Texas Motor Speedway next weekend.
"We are not playing around. I'm very confident in my team," Castroneves said.
The three-time Indianapolis 500 winner was 0.060 seconds behind Ryan Hunter-Reay at the Indianapolis 500 and likes his chances with an improved car on ovals.
"We know what we got, especially after Indy," Castroneves said.
Power, who won Saturday in the first of two races at the Detroit Grand Prix, says Castroneves has gotten better with age.
The bubbly Brazilian agrees.
"I'm able to pay attention in details that I haven't seen before, able to work with engineers better than before," Castroneves said.
Here are five other things of note as the IndyCar series shifts to Texas.
DETROIT DOUBLE: The Detroit Grand Prix was the first of three doubleheaders this year and also expects to host two IndyCar races on Belle Isle over a weekend next year. Much-needed improvements are coming to the street circuit as part of $4 million in planned improvements for Belle Isle, which looked spectacular in the middle of the Detroit River during the broadcasts.
POWER POINTS: Power leads Castroneves by 40 points in the standings and Hunter-Reay fell to third after a rough weekend following his Indianapolis 500 win. Power acknowledged he didn't race aggressively against Castroneves after a late restart because he did not want to risk a crash with his teammate. Power won his second race of the season Saturday and might have won again Sunday if he hadn't gotten penalized for avoidable contact on the opening lap, failing to turn right and causing Josef Newgarden to hit him from behind to trigger a three-car crash. Power said he would have to see the replay to say if he could have avoided it.
ROUGH WEEKEND: Hunter-Reay talked about turning the page after his "surreal" experience of winning the Indy 500 when he arrived in the Motor City. He left wanting to forget what just happened to him. Hunter-Reay started 21st in the 22-car field on Saturday, and Sunday because he kept hitting walls in qualifying. Hunter-Reay ended the first race by crashing on the final lap and the second one did not last as long due to an electrical problem knocking him out after 61 laps.
RAHAL'S REALITY: Graham Rahal wondered out loud about his lack of luck this season after finally finishing second on Saturday. His good fortune didn't last long. Rahal ended up being part of the three-car crash spawned by Newgarden's spin in the fourth turn of the opening lap of Sunday's race. He clipped the wall on Lap 50 and finished 21st in the 22-car field.
CHEVY SHINES: Chevrolet brought auto racing back to the Motor City and has committed to keeping it on Belle Isle through 2016. The engine manufacturer produced a winner for a change in the shadows of corporate headquarters. Chevy swept the podium on Sunday and Power's Chevy-powered car won the first race of the weekend. Honda had won the previous three races in Detroit, earning eight of nine spots on the podium.
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