On my 78 Cobra I am running the 225 50 15 on the front on 15 x 8.5 rims but it had it's share of problems but have located a set of 14 x 6 5 bolt slots that will get fit with 225 or 235 60 14's after the restore, now comes the fun part the rears are on a 10 x 15 deep slot sporting 295 50 15's and yes they fit, had to build fender flares to keep it legal as I disliked the idea of mudflaps and with that setup i find it launches quite nicely
Steve seeing how you are planning on dropping the front end down a little I would suggest running a 14 inch 60 as I had rubbing problems after I stiffened the front end up and the ride sucked, cornered like a dream due to almost no body roll but the ride was very rough, I have the granada rotors and I think a 4.25 back spacing, even running a straight line with new coils up front the tires had words with the fenders till I stiffened the front end up but then it felt as I was driving with no motor as that is how stiff it became and tight corners like in a parking lot the tires will rub on inner fender but it does look sharp
I had a set of M/T 28/10.5/15 w 1/2 alum spacers...fit and looked great...didnt get to road test em...im assuming they would be ok if i kept under 250mph...haha...lookin to put 18-20s on the rear and 18 in the front...
