Quote:
Originally Posted by TahoeM3
There are a couple of reasons...a larger diameter tire has a longer (front to back) contact patch which helps forward traction, as opposed to a wider contact patch which helps lateral traction.
|
True. However I doubt that 4% on the diameter makes much of a difference
Quote:
Originally Posted by TahoeM3
A shorter, stiffer sidewall has less flex and it more prone to spin off the line, whereas a taller sidewall allows the tire to set on launch, helping the car move forward rather than just spin. Is is true when in motion, also. Ever notice how dragsters all have big rear tires with sidewalls that flex?
|
Also true. But to make a real difference, it would be better to go with an 18" wheel.
Quote:
Originally Posted by TahoeM3
And of course, there's the diameter itself. For each revolution of a tire, it covers a certain distance. The bigger the diameter, the more distance covered per revolution. This data is available on TireRack, which lists revs per mile. Of course, it is offset by weight, so a larger heavy tire can be slower than a small light tire, but all things equal, bigger diameter is better. You can imagine extreme cases where a tire is has a diameter of 1"...the car can rev as fast as it wants, but it will move forward slowly because each rev only moves it forward one inch. Compare that to a tire that has a diameter of 100", where the car moves forward 100" for each rev, and you can see how much faster it would be than the car with 1" diameter tires, assuming equal weight, etc. Of course, this also affects final drive ratio, but that's another discussion.
|
Here, I am not sure I follow you. It does have to do with the final drive ratio, it is not another discussion. Larger diameter tires equate to a taller final drive while smaller diameters equate to a shorter final drive. Period.