[200q20v] Re: [V8] V8 and 200q20v difference

[Phil Rose]

At 9:08 AM -0500 2/6/02, Michael L. Riebs wrote:
>  > Actually, my intent in asking whether tires would have something to do
>with
>>  mpg results was more in consideration of tire compounding/construction
>than
>>  in SIZE.
>
>Well, then my guess would be that the harder the tire, the better fuel
>economy, and a softer tire would be less economical. However, with the
>compounds we have available commercially, I doubt if there is a several mpg
>noticeable difference. Probably a little though!
>
>Michael Riebs
>Grand Rapids, MI
>'90 V8Q
>'98 A6QA
>

The biggest tire "construction" change in memory (mine, at least) was
the switch from bias ply to radial ply about 30 yrs ago. That
produced a quite considerable reduction in rolling resistance, which
(as I dimly recall) could allow a few mpg improvement. Nowadays, the
biggest tire-related variable for fuel economy is certainly inflation
pressure . This affects both the radius *and* rolling resistance,
which IMO might account for a several mpg effect. However drivers
often don't appreciate the mpg effect(s) of tire pressure since--as
already mentioned--any (+/-) radius change will produce an offsetting
odometer error, which obscures some of the actual change.

Phil
--

Phil Rose				Rochester, NY
'91 200q	(130 Kmiles, Lago blue)
'91 200q   (57 Kmiles, Tornado red)
	mailto:pjrose at frontiernet.net