|
As posted elsewhere, lower is not always more aerodynamic.
Depending on the shape of the bottom of the vehicle, higher can be just as good.
It seems the anecdotal evidence is mixed, and some of the gains reported may be due to odometer offsets due to the tire sizes as not everyone indicated they compensated/adjusted for that.
It's possible that small size changes fall within the mean error of testing compared to the changes of putting on new tires which obviously have a significant effect themselves.
Unless someone buys new tires of the same type in both old and larger sizes, and mounted them on identical sets of rims, this question may be difficult to answer. And even then we have to assume the tires are relatively equal.
|