A 14 inch wheel was stock for your car; but the same outside tire diameter existed with a 15 inch wheel (used with disc brakes). The same thing happened for the three years that the factory flirted with 16 inch wheels before switching over to 17 inch wheels (18 inch on the Corvette). In every case there is a tire that matches the 14 inch original tire's diameter so that the car sits at the same height. It ls has the same outside size so that your speedometer works, and the wheels and tires fit in the wheel wells.
What changes as the wheel diameter increases is that the height of the side wall shrinks and the ride gets worse as the side walls can not flex.
This is true for the twenty inch wheels and tires that fit on my pick-up as well. They are much taller than a twenty inch car wheel and tire, but they are the same outside diameter as the 16.5 inch wheel that this combo replaced on a pick-up. So if you put a 20 inch tire off of a pick-up truck on a 20 car wheel you couldn't get it in the wheel well as it is a foot taller than a car tire.