I did not catch they made the Dunlops in 215/40/17, must of overlooked it, that would help with the height and sidewall stiffness a great deal so they just might be the way to go since proven to work well on 7's, great input, thanks Forzda1
I did not say the RE-11 was not a good track tire, I only said it is not the best which has been highly documented by experts and racers.
It is likely the better choice on a wet track but on dry tracks is has shown to heat up and lose grip quickly.
If you looked at the SCCA national solo winners you will find who runs and wins with what tire and you can look at regional results, forums, etc...this is not rocket science nor something just pulled off the net, it is well proven information just like Forzda2 has just posted, real results, same car, same wheel width. Sometimes the best is to use a wider tire as mentioned, often times not.
Grassroots motorsports tested the current (at the time but not that long ago) fastest tires using a long time racer, winner, championship car and found the 225/45/15 Rival the fastest and considerably quicker on a 9" wheel over an 8" wheels. This was with many sets of wheels and tires, swapping quickly to keep the weather the most constant, timed laps, all done by very seasoned racers with decades of combined experience.
But, you have to work within the rules so stepping outside the absolute best solution but doing so with the most information will yield the best results for your particular needs and restrictions.
Listen to the experts, do the research, it is all out there and easy to find, as I have done so I can make educated recommendations on real results
Basically I have said the same thing a few times here so just wanted to clarify things a bit more since some comments seemed to show some confusion about all this. It all still stands and now you have some real results on this particular car, plenty of places to look and see what the truth is, have fun