Skip:
thanks for that generous offer. Thanks especially for that about the sheet
metal! (You don't think I'll be ready for my masters certificate any time soon?
Do they take off points for grumbling?)
Seriously, in many ways "Rose" would be an excellent test bed. She is fast,
stable, and reliable-- inherant to the design. No matter what engines you put
in
her, I think we can make her spin the wheels if we try-- and I don't think
she'll
try to kick our butts when we do it.
You said that you would expect most of the gain in the first two miles. I
believe that that is true for "Rose", unless you have at least 1000 hp per axle
in her. Like all the other cars that were able to approach their (chassis /
engine combination) potential this summer, aero resistance was one of the two
most important factors that said where that limit was. In some cases, the other
factor seemed to be that the drive tires could not generate enough friction to
accellerate against the resistance (those folks could benefit from TC right
now!). In Rose's case, however, I think the little bit of high-end wheelslip
that we saw was not a limiting factor. I think she mainly just wanted more
horsepower (she's pretty aerodynamic, for just the one BBC). As you add more
horsepower to her, I think she will obey the laws of physics and start showing
consistent wheelslip on the big end-- in which case, she would benefit from TC
on
that end, as well.
One challenge I see with the new (4WD streamliner) configuration is that there
is
no "free" wheel left from which to get a speed comparison. We could control off
the drop in torque that comes with wheelspin, but the control logic would be
harder to conceive & de-bug. And Dave would have to make some changes to the
circuit he is conceptualizing. I think a torque-based system is an interesting
challenge-- my mind is already "whirring" on how to find the point of chassis
strain that best characterizes (and isolates, hopefully!) torque-drop, and what
sensor to use. (I'm thinking somewhere on each engine frontplate-- pinpointed
using brittle laquer during a test-run-- and instrumented with a simple
strain-gage. Needs a "bridge" circuit for measurement.) Let's see what Dave
has to say!
Re the "tire failure analysis" idea-- if you get the tires, I will get us an
expert volunteer.
Best Regards,
Russ
Skip Higginbotham wrote:
> Russ, Dave and List,
> If anyone wants to build a system and use "Rose" as a test bed (4wd
> uncoupled pairs), let me know and I will try to figure out how to install
> it (Russ, you know the car) and get a "test" authorization from the powers
> that be. I may be surprised at the outcome but believe that most of the
> improvement will be evidenced in the first 2 miles of the course.
>
> I'm still interested in tire failure analysis.......to be able to properly
> focus this on safety. If Traction Control proves to be a safety enhancing
> item in terms of preventing tire failure, I'm all for it.
>
> Skip (Still no opinion but seeking truth)(I'll do the sheet metal!)
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