Moderator: volvite
The tires are the same height giving the same rotation, only not as wide. How wide a tire is will not effect the speedometer or tripometer, only making a tire taller or shorter would make a difference. Say change a car that came with 16" tires to 12" tires (don't laugh, I have seen that) would make a difference, in this example it would be a BIG difference.NVSteve wrote:It's most probably the fact that the speedo/trip are no longer accurate. The smaller the tire from stock, the higher the mpg gain (according to the speedo/trip/odo), when in reality it isn't.Calicajun wrote:thinks she is getting a little better gas mileage.
Oh, I'm following you. My point, which I didn't make very clear, is that a lot of the cars driving around on the roads today are giving false/inaccurate mpg readings because most vehicles' electronics and calibrations are based on one tire size only. Even if your new vehicle comes with tires of a certain size, that does not necessarily mean that the electronics are calibrated to that exact tire size, especially if other models/packages exist for that same vehicle that offer different tire sizes. I've driven a few rental cars that were not accurate, but couldn't for the life of me imagine those particular vehicles had other options available (tire sizes, etc) because, well, they suck so bad to begin with. I think it is a fully deceptive activity on the part of the mfrs.Calicajun wrote:
The tires are the same height giving the same rotation, only not as wide. How wide a tire is will not effect the speedometer or tripometer, only making a tire taller or shorter would make a difference. Say change a car that came with 16" tires to 12" tires (don't laugh, I have seen that) would make a difference, in this example it would be a BIG difference.