Throttle-by-Wire

[Bruce]

From: "Asylist" <chevynova at peoplepc.com>
> > Or do you mean publicly admit to it?.
> > If the lose of adhesion helps a car go faster, then there are
> > other issues.
> > In talking oems most deactivate at 35 or 40 MPH.

> With most of my experience being on the dragstrip, I'll speak there first.
> I can consisitently get ETs by getting some wheelspin out of the hole.

Most TC allow for some wheel spin.  They just min it..

>This
> way I can keep the engine in the power band when launching.  Its kind of
> like a poor-mans high stall converter.

OK, but why slow the car down, there is very fine line from min to excessive
wheelspin.   You'll always be faster with a min of wheelspin.  Using TC to
compensate for the srong converter, is a bandaid, not a cure.

>Yeah, you're right, there are other
> issues.  Like not being able to afford to dedicate a car to the strip, and
> setting it up properly.  I'm stuck with a dual purpose car.  By
definition,
> TC eliminates wheelspin.  Many times this will result in bogging the
engine,
> and little power off the line.

Those symptoms are for a poor execution, not a poor design.

> I've seen extremes by as much as a full
> second in 1/4 mile times between TC on and off.  There are similar issues
on
> a roadcourse-a little bit of a powerslide helps to keep the RPMs and
> momentum up.  Unless you have gobs of power available, with high grip race
> tires, slowing down enough to prevent the tires from losing traction could
> result in adding a good amount of time to the lap times.  Most factory TC
> systems just aren't designed for quickest track times.  They are designed
> for maximum control on the street.

Road and track had an interesting article about TC and yaw control some time
ago, I'd suggest finding a copy of that and you might be really interested
in what the good systems do and how they do it.
Bruce


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