Let's see: lose significant fuel savings, probably slightly more power with e85 and meth on a car you want to track is silly. Why add a whole additional layer of things that could go wrong to your fuel system? The kits are better than they used to, but not suitable for running at the track. You have electrical connections, another tank of flammable liquid in your trunk, another pump that could fail and then it still needs to be setup and tuned right.
E85 could get you to 104 unleaded power levels + much cheaper than race gas costs