If you are going to spend a lot of times in the corners, I would stick with a square setup. Unless you have an unlimited budget for tires. Being able to rotate your wheels around the car helps longevity.
Depending how crazy you are going to get. BUT
I would just get the cheapest GT you can find. You will end up replacing anything and everything that makes up the "track pack" or other packages so no point in wasting that money up front.
Picked up 10 19" pzero slicks off a Ferrari challenge car to use on my factory wheels, one one heat cycle. 255/650/19
BUT I am changing plans and going with a enkei nt03 wheels 18x9.5.
A married/locked x4. They can go for as little as 100 bucks. I tuned mine on hptuners but carry a locked x4 in the car to data log or check ethanol content etc.
Any thing close to or above 275 degrees can be seriously dropping the oils Wear Protection Capability. Could be as high as 30%.
I wouldn't allow it to get that hot period, no reason too.
Had some pretty serious overheating on the track, after 6 laps or so cylinder head temps were in the 248 range. I really need to get a water temp sensor on this thing as well as a oil temp gauge. Going to turn my fans on much lower and keep them on.
First on my list is to get everything...
i tuned the car and enabled flex fuel and had been pretty awesome. First track day I didnt believe I would go throw two tanks of fuel, started the morning with full tank of e85 and the track only has 91 so ended up with a fuel tank of gas.