The Z06 is already on the ragged edge (and for many unlucky folks, over it) of the capability of the OEM cooling solution for track work. I'm talking about actual coolant and oil temps and not charge air temps. It handles charge air temps reasonably well. Dumping the waste heat to make 100 more HP in to the OEM air and oil cooling though is not going to be a pretty sight for anyone who tracks their car.
Callaway usually does a pretty good job, but this car would only be a good street or drag car. They haven't touched the primary engine cooling at all.