From Wiki:
Although the ZR-1 was extremely quick for its time (0-60 mph in 4.4 seconds, and onto 180+ mph), the huge performance of the LT5 engine was matched by its robustness. As evidence of this, a stock ZR-1 set seven international and world records at a test track in Fort Stockton, Texas on March 1, 1990, verified by the FIA (Fédération Internationale de l'Automobile) for the group II, class 11 category:[8] [9]
100 miles (160 km) at 175.600 mph (282.601 km/h)
500 miles (800 km) at 175.503 mph (282.445 km/h)
1,000 miles (1,600 km) at 174.428 mph (280.715 km/h)
5,000 km (3,100 mi) at 175.710 mph (282.778 km/h) (World Record)
5,000 miles (8,000 km) at 173.791 mph (279.690 km/h) (World Record)
12 Hours Endurance at 175.523 mph (282.477 km/h)
24 Hours Endurance at 175.885 mph (283.059 km/h) for 4,221.256 miles (6,793.453 km) (World Record)