I think I know what you are trying to accomplish. You'd like to 'fill' as much of the wheel well as you can. Fitting a larger overall tire setup will accomplish this, but there are too many drawbacks. I don't know that exact limitations, but keep in mind that if you are too drastic with your decision, you may end up rubbing the fenders with the tire during hard cornering, or when your car is loading with passengers. I'd suggest you purchase a setup that will give you the same overall diameter as the stock one, but with 17" rims. I need to know what your stock setup is first, before I make a suggestion. If you keep the same diameter, than save up to have your Tiburon lowered, that way the space around your wheel is minimized, plus you get better handling/cornering capabilities.