Joao Barbosa and teammate Darren Law led an Action Express 1-2 at the Detroit 200 on the Belle Isle street circuit.
Barbosa and Law took advantage of their rivals misfortunes in the pits to take their first win of the season.
"It was an interesting race," said Barbosa, who was at the wheel of the No. 9 Action Express Corvette DP when it took the lead, 19 laps from the finish. "We had a great car and […] were really motivated to get a good result for Chevy here in Detroit."
David Donohue and Terry Borcheller came in second, aboard the No. 5 Action Express Corvette. Scott Pruett and Memo Rojas, in the No. 01 Telmex BMW/Riley finished third.
In the GT class, Jordan Taylor and his teammate Paul Edwards drove the No. 88 Authohaus Motorsports Camaro GT.R to the win. Rivals Dion von Moltke (No. 51 Audi R8) and Guy Cosmo (No. 03 Ferrari 458) took themselves out of contention; von Moltke by crashing, Cosmo by jumping a restart.
Jonathan Bomarito and Sylvain Tremblay (No. 70 Mazda RX-8) and Robin Liddell and John Edwards (No. 57 Chevrolet Camaro GT.R) round up the top three.
Race results – Grand-Am (Detroit)
1 - Barbosa-Law (Corvette DP) - ActionExpress - 72 laps
2 - Donohue-Borcheller (Corvette DP) - ActionExpress - 72
3 - Pruett-Rojas (Riley-BMW) - Ganassi - 72
4 - Fogarty-Gurney (Corvette DP) - Stallings - 72
5 - Negri-Pew (Riley-Ford) - Shank - 72
6 - Dalziel-Potolicchio (Riley-Ford) - Starworks - 72
7 - Luhr-Popow (Riley-Ford) - Starworks - 72
8 - Braun-Mayer (Riley-Ford) - Starworks - 71
9 - Edwards-Taylor (Chevy Camaro) - Autohaus - 70
10 - Bomarito-Tremblay (Mazda RX8) - Speedsource - 70
11 - Edwards-Liddell (Chevy Camaro) - Stevenson - 70
12 - Assentato-Segal (Ferrari458) - AIM - 70
13 - Auberlen-Dalla Lana (BMW M3) - Turner - 70
14 - Lally-Potter (Porsche 997) - Magnus - 70
15 - Sharp-Cosmo (Ferrari 458) - Extreme Speed - 70
16 - Cameron-Nonnamaker (Mazda RX8) - Sahlen - 69
17 - Nonnamaker-Nonnamaker-Nonnamaker (Mazda RX8) - Sahlen - 69 18 - Foss-Lindsey (Porsche 997) - Horton - 68
19 - Norman-Von Moltke (Audi R8) - APR - 68
20 - Curran-Said (Corvette) - Marsh - 67
1. Dalziel, Potolicchio 142; 2. Law 138; 3. Donohue, Pew, Rojas, Negri, Pew 138.