Are you runnig 18" wheels? most tarmac rally tyres are 18"
Hankook rs2 are the cheapest track tyre I have ever found! not as grippy as R888's, but very hard wearing!
Road tyres will over heat and bead, and lumps will fall out of them if you stay out for to long!
Run plenty of neg camber to stop the outside edges front scrubbing away!
Dan