Helio Castroneves, driver of the No. 3 Hitachi Team Penske Chevrolet, climbs the fence to celebrate with teammates after his victory Sunday during the second of two IndyCar races on Belle Isle in Detroit. Chevrolet swept the podium with first dual winner Will Power, driver of the No. 12 Verizon Team Penske Chevrolet finishing in second-place, and Charlie Kimball, driver of the No. 83 Novo Nordisk Ganassi Racing Chevrolet taking third. (Photo by F. Peirce Williams/LAT for Chevy Racing)

Helio Castroneves, driver of the No. 3 Hitachi Team Penske Chevrolet IndyCar V6, was the third fastest in combined practice sessions Friday for the Detroit Grand Prix on Belle Isle.  Castroneves is third in IndyCar Series points.  Simon Pagenaud paced the practice session in the No. 77 Honda. (Photo by Phillip Abbott/LAT for Chevy Racing)

Jack Roush signs autographs at MIS. Dave Marr photo

Jack Roush has an plan.
But he's not sure he wants NASCAR to follow it.
The owner of Roush Fenway Racing wants the stock-car sanctioning body to inspect and send to a wind tunnel two cars from each manufacturer following each Sprint Cup race.
That way, Roush believes, everyone will know whether Ford, Chevrolet or Toyota has an advantage over the others in important areas like downforce.
"They don't want to introduce a reason why one manufacturer has an advantage," Roush, whose company owns three Ford-backed Sprint Cup teams, said Sunday, explaining why he doesn't think NASCAR will take up his idea.
Competition in Sprint Cup racing is close, Roush said, noting that all three manufacturers placed a car in the front two rows for the start of the Pure Michigan 400 at Michigan International Speedway.
"I think NASCAR is happy with that," Roush said.
What makes Roush nervous about NASCAR checking out two cars from each manufacturer after each race?
"My fear is that they might do the test and find that Ford is not at a disadvantage," Roush said.