
You shouldn't have fitment issues if you've already rolled the rear - im running 235/40's with RX8's and haven't rolled the rear yet but have been getting cuts in the tyres - i also have no finger space in the rear guards.
im running Federal 595's I picked up off ebay new $500 can get you a link if your interested. they are fine for my driving to and from work

is it just cuts in the rears or the front also? and also, is your car lowered?

cuts on rear only, but that will get fixed once I roll the rear.
Yes lowered on Yellowspeed coilovers why I don't have any gap in the rear - set on pretty stock stiffness so if I stiffened it up it might prevent, but it only srubs on big dips/drops otherwise normal driving is fine.

thanks mate, appreciate your help since my guards are rolled im confident i can fit 235/40/18
hmm thanks anyway for the federals - might just stick to the Kumho's considering it all comes with a fit and balance
just haggled with Big O tyres to give me Kumho KU27's for $145.00 a pop - they say KU27's are better than KU31's aswell

no problems, yeah you'll be fine with 235's and rolled rears then
you lowered any?

Yea i bought the care lowered - the guy before the guy i bought it from compressed the springs (not the ideal way to do it) but cbf changing it until i have a cash to spend - I can fit 225/30/20's and theres no more room even for my finger but i dont get any cut or touching either