I have 245/50/16 front and 255/50/16 in the rear on my zq8 with 2/3 drop with no rubbing at all. These tires are pretty wide and they hold the road very well. If it interests you the tires I have are Falken Ziex ZE512. They were only like 70 or 80 a piece and I didn't pay shipping (Discounttire.com).
falken ziex 512 is a nice tire. i am also running them on my 02 blazer xtreme in stock 235/60/16. they hadle pretty well for how heavy it is.been running them for about 8,000 miles now and they still have plenty of life in them. my truck hits the front of the framerail if fully clocked . gm was great for not checking steering clearances when assembling these trucks. some trucks hit,some dont.so you wont know how it will be till you mount them. i am also at stock xtreme hieght