Wally,
Sure, you Vette guys are always braggin' about doing 130mph and stuff...
;-)
The database of car specs doesn't effect speed; it actually works the
other way around. Speed is calculated just by integrating the
acceleration over time. The car specs are then used to calculate back
RPM and HP, if you should pull up the gages for these items. So that's
not why you are going 130 at the end of your run.
The 130mph at the end of your run is probably a result of drift in the
turns. This is a normal problem, and one which we have easy adjustments
for in the software.
Here's what causes it. If you can imagine your car as it goes around a
big radius with no slide, you can see that the lateral g's are applied
perpendicular to the car. That is, they are being applied at 90 degrees
to the car. Now imagine the car being just a bit tail out, say 5
degrees. Now the lateral g's are being applied mostly laterally, but
with a portion being recorded along the longitudinal axis of the car.
This amount is equal to the sin(slipangle) * actualg's, or in our
5 degree tail out example, 1.00 g lateral acceleration produces an
additional 0.08g's of acceleration! Thankfully, we don't drive the
whole course at 5 degrees of slip angle, but we often do hit those
angles enough to produce a significantly higher end speed than is real.
The solution is to use the adjustment dialog. As Dick pointed out, for
the most thorough explanation of how to use the adjustments, go to the
Wizard's Tutorial in the Help Screens by that name. It'll take you
through step by step. But the quick and easy answer is to click on the
adjustments button, and click on the SLOWER side of the END SPEED slide
bar. This will decrease your end speed by decreasing the lateral g's at
each point by a set amount.
BTW, Dick described a process of saving your run before adjustments so
that you can return to that if you need to. I don't do that. Instead,
if I screw one up beyond all recognition, I just go back and reset all
of the adjustments back to zero. This will return you to your starting
point, and keeps you from having to make two copies of each map to
start. The only thing that this won't fix, is a bad trim. If you cut
part of your map off, by marking a block and deleting it, that block is
truly gone. In this case, the program will prompt you if you want to
save the run again, and overwrite the old. If you do, that change is
permanant, so be sure you cut it right before you save it.
--Byron
Wally Strzelec wrote:
>
> I am a real geez novice and started looking at my first recordings today.
>
> I notice that there is a data base that you can put in car specifications.
> Is this data used any where? I do not see any place to correlate a run with
> car specifications, or have I missed something?
>
> Could this be why I am finishing the course at 130mph?
>
> -Wally
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