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Old 04-18-2011, 07:32 AM   #39 (permalink)
CapriRacer
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Quote:
Originally Posted by zonker View Post
Prior to reading capri racers conclusion that wider and taller tires will improve FE, I was planning on mounting a set of 15x4 alloy rims with 165/80-15 VW Beetle tires in the efforts of getting the ultimate FE tire/wheel combination for my 'stang.

hmm... i think i have an opportunity to do an ABA test of the effects of larger tires on my mustang ragtop.

I have another mustang with the same exact 14" polycast wheels as whats on the white rag now, except the tires mounted on it are 215/70-14 radials instead of the 195/75-14 tires i am using now.

I'll weigh the both wheel/tire combos and then do my 92.6 mile FE run back to back and see if the 215's will yield better FE numbers.
Word of caution. A-B-A testing means everything else remains the same.

One of the things that clouds this issue is the differences between tires.

http://www.energy.ca.gov/transportat...%20Testing.pdf


This says there can be as much as a 60% difference between tires of the same size. The effect that is important - the difference in F/E caused by tire width alone - is pretty small - 0.1%. This means any test has got to eliminate differences in tires or the effect will be unobservable.

Zonker, if you are going to do this test you need to make sure you have otherwise identical tires - same make, model, and state of wear (New would be good).

And because OE tires are NOT usually identical even within a line of tires, it might be good to post what tires you are considering using BEFORE you conduct the test. I can steer you away from potentially different tires.

It would be bad if you spent all the time and effort to conduct the test only to have the results invalidated because of a poor selection of tires.
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