I may be kinda beating a dead horse here....
I have 17"x9" wheels, and I'm running 275/40/17s all the way around. I'm getting more into circle track stuff, and they're awesome! (Not comp tires, but I'd highly recommend these BF Goodrich g-Force Sports for daily driving. Awesome.) I have
Eibach Sportline lowering springs and a caster/camber kit as well.
However, if you're going to run 10.5" wheels - get 315s!! Or at least, definitely DON'T get 275s. Way skinny...besides, the point of getting those wheels is to run a bigger tire. I have three different friends that run 315s on 10.5" wheels (granted, 2 are F-body) and they love them. None of them complain about their contact patch a bit.
Best of luck to ya!