We aren't allowed sphericals.
I believe min ride height is 3"
One of the things we played with at Barber this past weekend was front ride height.... Running some quick in and outs after baselining the car/setup.
I can say this... For our particular setup there is a "sweet spot" on ride height. When we even went 1 complete turn up on the front springs ... It brought on an understeer.
Barber is a tough track... but a great one to try stuff on... even on old tires.