Where is the big skid pad?

Speeds of 100+ mph are needed to really test aero, and tune driver skill. A skid pad is needed to go over the limit safely.

Math
a = v*2/r a - acceleration, v=velocity, r=radius of turn

For acceleration of 2 G's at 100 mph the radius is 336 feet. Add some runoff and a skid pad of 800' x 800' is needed.

Streets of Willow skid pad is 400' x 350'. I got my kart up to 2.5 G's on a 100' radius at 61 mph.