Can a Yaris fit 13" wheels??

[RUFFSTUFF]

Originally Posted by TheRealEnth

oh... cause i ask because, my yaris no longer hits the 118mph mark, i can bring it up to 105 or so... and i never knew the cause, ive tried new air filter and such. could that be a reason?

If you made a wheel and/or tire change that resulted in a lower diameter then your actual speed will change accordingly. As a note, aspect ratio (i.e. 40,45,60, etc) is the ratio of the sidewall height to the tread width. So a 185/60-14 would measure as 185mm wide, 185 * 60% = 111mm sidewall height on a 14" wheel... 14" is about 356mm so overall diameter would be 356 + 111(2) = 578mm or about 22.8 inches. The rolling circumference would be 1816mm.

Change the aspect ratio on that tire to 55 and the diameter changes to 560mm. The circumference would be 1758mm. That's a reduction of 3.2% from the 60 series. Theoretically, since your speedo doesn't register the tire change, this scenario would result in the car going 3.2% slower at the limiter.

Also of note, that if not limited electronically, the change in gearing can actually let the car travel faster by placing the hp peak at a point where the frictional losses of air resistance can be overcome... i.e. the car will be able to rev out...

Actual results may vary.