Here's a little more insight on the run around Nurburgring.
http://autos.yahoo.com/blogs/motoram...230536466.html
"....
Chevy says the run was part of what it calls a "24-hour test" — running a day's worth of laps at various tracks, with only brake and tire changes allowed, to measure a car's durability. And based on the data from the wet lap, Camaro chief engineer Al Oppenheiser contends the Z/28 could have gone a couple seconds faster on a dry track. ..."