> I wanted to see a 225/50-15 vs 225/45-16 vs 225/40-17 R-tire test on
> identical make 8 inch wide wheels, and I said I thought the 15's would be
> fastest (on a real auto-x course, not one where half the course is a
> big circle).
It would have been nice to do it that way, unfortunately the test was not
available that way. Just like I know when I test different sway bar
combinations I would like to have more bars to test width, but have to be
objective with what I have in order to make a good decision for the next one
to be made.
I do not think the course mattered as much. Any autox couse you will be
sustain alot of lateral G's, compared to acceleration G's. SO if is a skid
pad or if it would have been four 90s in a row I do not think it would have
changed the results.
The 15s were at a width disadvantage but I do not think the width would have
made up all the time difference on my times. Yes this course might not be as
long as some of our courses, but all you have to do is percentage out the
margin to what you think would be adequate. I think on the course used a
tenth was much harder to get than on a typical course, since it was short.
So in your mind it might help to think as a tenth more like two tenths.
> The 15's would be the lightest combo, and sidewall height
> would be less of a factor (almost none) with a stiff R tire.
Yes that is not as much as a factor. The test might have been more beneficial
to some if R tires were used, but they wanted to try to appeal to the ST
racers particularly with this article.
I am not an engineer, but a tire turning more slowly I would assume has more
capablility to pull lateral G's, I would assume would be a factor. You have
picked on some obvious factors, but there are more factors involved also in
my opinion.
> I thought Hoosier didn't have the 245/50-15 out then, that's why the car
> had 245/45/16's. Hmmm...
You may know more than me from talking to him, but it just rest assured at
least in my mind that he was not hindering himself compared to the 13s, 14s
or 15s.
--BRian Priebe
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