now i like a little stretch for practicalitys sake, a 165 65 13 is safe to go onto a 6 inch rim according to michilin, but not good year, go figure but a 155 70 13 is safe on a 13 x 4 or 4.5 incher.

no way would i consider a 175 70 13 or a 185 60 13 safe on a 13 x 8 inhers or so... some ae86 guys run 175 70 and on 13 x 7 and 8.... and due to the larger side wall thats where i have heard of tyres rolling off the bead, seems with more potential side wall flex its possible but where i say it was 205 45 16 on a 8.5 inch rim, silvia guys love this and does not look great when it happens