The No. 70 Speedsource Syntec Castrol Mazda RX-8, left, chases the No. 68 TRG Porsche GT3 on the IMS road course during Grand-Am testing. Photo Credit: (Indianapolis Motor Speedway) hide

The No. 70 Speedsource Syntec Castrol Mazda RX-8, left, chases the No. 68 TRG Porsche GT3 on the IMS road course during Grand-Am... more