Complex sentence: He currently drives the No.4 Chevrolet SS for Stewart-Haas Racing in the NASCAR Sprint Cup Series and he also competes part-time in the Xfinity Series, driving the No.88 Chevrolet Camaro for JR Motorsports.
Split into simpler sentences: He currently drives the No.4 Chevrolet SS for Stewart-Haas Racing in the NASCAR Sprint Cup Series. He also competes part-time in the Xfinity Series, driving the No.88 Chevrolet Camaro for JR Motorsports.