steve preston wrote:
> I don`t really understand that,Bill! I always thought
> that smaller diameter tires required more engine rpm
> to cover the same ground. It seems that any reduction
> in that diameter would have to speed up the engine at
> least a little bit. I guess maybe a less aggressive
> tread design could reduce drag,and that could be
> enough to offset the difference. I don`t know. I went
> a size UP (from 70 to 75R) on my tires (last
> year?),just to make the truck sit a little higher and
> take up some wheel well space. Also to save a little
> money! But I neglected to measure mileage before and
> after,which I wish I`d have done now. Steve
> P.
Guy at work said to me "oh you are going to lose fuel economy by going
to those bigger tires" when I informed him I planned to stuff 35 inch
shoes under the Ram.
While it may be true that I would be rolling around with more weight and
the engine would have to use more power to turn bigger wheels - they are
not that much bigger - I have approx. 32's now - stock. Also the loss of
aerodynamics isnt that much to worry about either. This truck already
has the aerodynamics of a skyscraper.
I may see a loss in city driving - but a larger tire will rotate less
times than a smaller tire and will in turn lower the number of RPM's the
engine runs at while at highway cruising speeds. (final drive ratio)
This is where I am looking to make my primary gains. The way I drive -
I know I have a snowballs chance in hell, to get good MPG figures in
town. I'm in the process of getting a more economical means of
transportation around town.
-- -------------------------------------------------------------- ***** Countdown to 2004 DML BBQ (63) Days Left! *****Terrible Tom -- AIM & Yahoo Name: SilverEightynine http://members.aol.com/silvereightynine/
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