Okay, I wanna pick up some new rims...probably not until next spring unless I come across a really good deal, but anyways..

I remember reading something at Suburban Tire one time while I was there with my last car, and in the brochure, it said something about putting a tire that is 1" (rim size) smaller onto a rim to give it a more "aggressive" look and something about performance (probably less sidewall flexing).

Anyways, I was curious if anyone else has ever heard of this, and do you think it would be okay to put my Kumho Supra 712 P245/50ZR16 tires onto 17" 4th gen rims?

 

You read wrong. It cannot be done. Maybe they were refering to the overall tire height being 1" shorter.

 

The were referring to oversizing or using bigger rims and tires then the factory. What you said can't be done.

 

Hmm...I'll have to run over there one of these days and see if they still have the brochure. I didn't think it made much sense either when I read it. I just remembered it a little while ago and figured I would ask about it because I didn't think it sounded too viable either.

 

You may have read it wrong. It may have said Plus 1 size which is going from a 16" rim and tire to a 17" rim and tire and keeping the tire height the same.


This is from discount tire direct,
" Plus sizing is one of the easiest ways to achieve enhanced performance and improve the appearance of your vehicle. In the example above, a 15x7 wheel with a 205/65R-15 tire is considered the O.E. (original equipment) size. Converting to a plus 1 size would mean increasing the wheel diameter by 1" (16x7.5) and selecting an appropriate tire to fit (225/55R-16). Likewise, moving to a plus 2 fitment would result in a 17x8 wheel and a 245/45R-17 tire. It is important to note that although the wheel diameter is increasing, the overall diameter of the tire remains consistent. As a matter of fact, this method typically maintains the overall diameter of the tire within +/- .04 inches. This is crucial to preserving the speedometer reading and gear ratio.

A couple of things happen with the tire to increase performance when we begin to move into plus sizes. First, the tire is wider (section width) and therefore gives us a larger footprint. Second, the sidewall becomes shorter (aspect ratio) and more rigid. The two added together give better lateral stability and increased steering response."

 

Aw damnit I'll bet that is it. LOL! I completely understand how that works, I've done the math a ton of times for my buddy's Nissan.. oh well..