Scott Dixon and Chip Ganassi’s team turned the table on Hélio Castroneves and Team Penske last weekend in a pair of races on a typically rough, bumpy IndyCar street circuit in Houston. Dixon won Saturday’s race and finished a close second to Will Power in Sunday’s race while Castroneves ran into gearbox trouble in both, scraping home many laps behind in 18th and 23rd places.

Scott Dixon, the new championship leader

As a result, Dixon leaps from trailing championship rival Castroneves by 49 points prior to last weekend to enjoying a 25 point lead going into IndyCar’s season-closing 500-mile race at the California Speedway in two weeks. But the championship was the last thing on most minds following a terrible multi-car accident on the last lap of Sunday’s race in Houston.

After getting wide at the start of the lap Takuma Sato was struggling with rubber pick-up and lost a couple of places as he slithered around on the bumpy, slippery track. In the middle of a fast, blind sweeper Sato’s car slid into the path of the closely pursuing Dario Franchitti whose car was launched violently into the catch fence. Franchitti cartwheeled wildly along the fence with debris flying into the grandstands and there were fears as it took a few minutes to remove him from the wreckage.

Everyone breathed a sigh of relief when Chip Ganassi returned on his mini-bike from the accident scene to report that Franchitti was shaken and knocked around, complaining of pain in an ankle and his back, but not seriously injured. Dario was taken by ambulance to Memorial Hermann Texas Medical Center in Houston where he was treated for a concussion, a spinal fracture that will not require surgery and a fracture to his right ankle. As many as 15 spectators and one race official were also treated for minor injuries.

The remains of Franchitti’s car

Power and Dixon pulled away from the field in the opening laps of Saturday’s race but Dixon beat Power out of the pits from the first round of stops after Power lost a second because of a jack problem. Dixon got even luckier at the second series of stops when a full-course yellow flew just after Scott left the pits, trapping Power behind the pace car. Power stayed out for a few laps after the restart but fell down the order when he stopped, eventually finishing 12th.

Meanwhile Dixon drove away on his own to score his fourth win of the year and cut Castoneves’s point lead from 49 to eight. “It’s nice to be back on top of the podium,” Dixon said. “We got a little lucky with the yellow but I had a fantastic car, very similar to Toronto where you could maintain pace and put the gas down when you needed to.”

Simona de Silvestro drove an excellent race to finish second, beating Justin Wilson, Simon Pagenaud and Josef Newgarden. The 25 year old Swiss lady has been racing Indycars for four years and this was her first podium. She’s run well in many races and showed her stuff on Houston’s rough streets, cooly outbraking Pagenaud and Wilson in her climb to second.

Championship leader Castroneves qualified a disappointing 22nd for Saturday’s race and quickly ran into gearbox trouble. Helio had finished every lap this year until Houston but his record was ruined by a nine minute stop to replace his transmission’s gear stack. He rejoined 10 laps down to finish 18th.

Castroneves hits a bump and damages his gearbox

Sunday’s race was again all about Dixon and Power with Dixon leading early before Power passed him shortly after a restart. Thereafter, through a series of incidents and restarts, Power and Dixon dominated the race with Power scoring his second win of the year and Dixon taking the championship lead. James Hinchcliffe drove a good race on Sunday to finish third ahead of Justin Wilson.

Meanwhile, Castroneves ran into more gearbox trouble. Early in the race his car lost its underside gearbox cover when he took a wild ride over one of the bigger bumps. After trailing an increasing cloud of oil for a few laps Castroneves had to creep into the pits where his team dug into replacing their car’s transmission and rear end. He eventually rejoined, slogging home 37 laps behind in 23rd place.

In addition to taking the championship lead with Dixon, Chip Ganassi announced in Houston that he’s hired this year’s Indy 500 winner Tony Kanaan for next year. Kanaan will drive a fourth Ganassi car next year beside Dixon, Franchitti and Charlie Kimball. Kanaan spent most of his IndyCar career with Michael Andretti’s team before driving for KV Racing the past three years.

Tony Kanaan, who will be a Ganassi driver next year

Ganassi also announced in Houston that his team will switch next year from Honda to Chevrolet engines. Ganassi’s IRL/IndyCar team has run Honda engines since 2006 (and also from 1996-’99) and has been Honda’s lead team the past two years under IndyCar’s new 2.2-litre turbo V6 formula. At the California Speedway in two weeks Dixon and Ganassi hope to win not only IndyCar’s drivers’ championship but also bid sayonara to Honda by taking the manufacturer’s title in their last race together.

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