Originally Posted by synolimit

Because 285 on a 9.5" is not massive, many many many people run it! Lol how do you not know anyone? Spoon, Martin, Mike, chrisslicks, are just 4 off the top of my head, and because you suggested such a large rear with such a small front. These cars handle worse with stagger. 285/285 would be best. If you and he insist on a 305 rear you need to be at or lower than the stock stagger which is 30mm.

You can safely run 20% more tire than wheel, everyone knows this. A 9.5" is good to 285, 10.5" is good to 320, and 11" is good to 335. Also I wouldn't run more than 0.5" tire diameter difference front to rear on these cars.