Sorry Jay, I had always attributed this to Byron alone.
Additional comments below:
Byron Short wrote:
>
> Gary,
>
> Jay and I are using the same formula--it was actually the formula that
> we worked on together several years ago, with Jay doing all the actual
> work (and me getting most of the credit--people shouldn't make that
> mistake--Jay is brilliant at this stuff. My part was comparatively
> trivial).
> Your description would indicate that the slalom formula wouldn't really
> apply. The first cone and last cones of slaloms are blow-offs, and not
> subject to our formula. Including these in the timing can have quite an
> effect on the speed. Consider the most extreme example--a two cone
> slalom. Speed is actually infinite. Even in a three cones slalom, any
> autocrosser knows how to beat the formula. Our formula is designed for
> the theoretical never-ending perpetual slalom (a course no doubt
> designed by Karen Babb herself).
This would depend on available entry angle and attainable entry speed,
but I certainly see what you mean. In the testing I do we use a very
narrow, long entry and exit "gate" (at the same spacing - not timed) to
virtually eliminate anything other than a nearly straight on approach/exit.
There was no entry gate in the magazine test, but I approached it as if
there was because I'm so used to doing so (I drove in the test).
> With all the factors known, and with the above warning that the formula
> doesn't work for your test setup, the results would have nonetheless
> worked out to 1.38g. Again, that's too high because of the
> configuration of your test. However, it still fits into the peak
> maximums that we're talking about. (1.38/1.15 = exactly a 20%
> increase). So I wouldn't hang my hat on 1.38 g's in the peaks as a
> result of that particular test, I would still say it's plausible under
> transitional loading.
I'd say it probably fits well because the approach I took is somewhat
similar to what it would have been had there been an additional cone on
each end before the timers. I find that getting the car into a slalom
rhythm before entering the timed section will produce the best numbers
for that section (this would not be the case if the run-up was timed).
>
> And to your other question. There's no spacing/speed at which a slalom
> turns becomes steady state. The time from cone to cone is fixed, so the
> transition time is fixed. Your speed goes up in direct proportion to
> the cone spacing. IOW, if the slalom test that the magazine ran on your
> car had been at 500 foot spacing instead of 100, you would have still
> produced the same time results for the same number of cones, and you
> would have still had the same fast transitions from behind the wheel.
> The only difference would have been that you'd have been travelling at
> 392mph. And probably puckering just a teensy bit more.
>
> --Byron
Actually, now that I read this I remember this discussion many years ago.
In actual practice of course, that entry speed (392) and slalom speed
would not attainable, so at some combination of dimensions and entry
speed the car would be turning relatively slowly. I'd still like to see a
definition that separated transient and steady state, as nothing is
really steady state in an autox. I agree with John that we constantly see
reports/claims for steady state cornering that are too high. Much is due
to the equipment not compensating for the factors he mentioned, but I
suspect the majority is simply confusing transitional events for steady
state.
Hmmmmm.
thanks,
Gary
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