On Wed, 19 Jul 2017 16:53:06 -0000 (UTC), Mad Roger
wrote:

On Wed, 19 Jul 2017 12:17:36 -0400,
Frank wrote:

I found it interesting and first sentence says it, "They look cool."

I agree that people do things for looks alone, but what is strange is that
there doesn't seem to be a single beneficial performance impact of an
overall larger diameter "tire-and-wheel assembly".

I wasn't expecting huge performance gains, but I would have expected at
least one or two benefits - and not all negatives based on the two articles
noted.

If the diameter of the wheel and tire assembly increases by one inch
overall due to the one-inch increase in rim size - and assuming everything
else is kept equal in materials and aspect ratio and tread width - then the
two articles stated...
+ The engine delivers ~25% less driving force to the wheel contact patch
+ Which results in a decrease in acceleration
+ And which decrease in fuel economy (presumably at all times)
+ And unsprung weight goes up by a few pounds

Depends on the rims. The 16 inch torque thrust rims on my ranger weigh
less than either the 14 inch "deerfoot" alloys from the factory OR the
stock steel wheels.Yess, the 235/70 LT tires DO weigh more than the
205/75 passenger tires that came on the truck

The main astounding number is the fact the torque felt at the wheels is
astoundingly less for a single inch in overall diameter change.

Presumably that torque loss happens at all speeds (why would it not?) so
that denies us the one intuitive performance advantage of highway MPG.

That depends ENTIRELY on the particular vehicle (some will get better
mileage, some worse - generally the higher powered cars gain, the
lower powered loose) and how the car is driven (usually an improvement
in "sane" steady speed generally level driving, and generally worse in
city or stop/start driving, or "leadfooting" on the highway)