Re: AWD und FWD

["Randall C. Markarian" <asenna@accessus.net>]

Al Powell wrote:
> 
> This make me stop a minute and think.  Randall, consider this - IMO,
> a car should be optimally designed for the drive system which it
> *has*.  F/R weight balance, placement of driveshafts and fuel tank,
> exhaust system, and many other variables must be taken into account.
> 
> So I suggest that your comment about using ONE car is not necessarily
> correct.  A car which is designed for FWD will have inherent weight
> and design characteristics because it WAS designed for FWD.  Same for
> RWD.  I don't think you CAN use a single vehicle as a base
> for comparisons.

Here is a question for the "suspension experts":  An _ideal_ car has a
specific F/R weight bias (50/50 ala M3) regardless of its drive wheels. 
Suspension calibrations are made largely on the weight of the vehicle,
weight distribution, center of gravity, and roll center of the vehicle;
regardless of drive wheels.  If the suspension is set up properly for
those characteristics, then that will expose the "flaws" of different
drive types on that "car".  The suspension is not sure what wheels are
driven.  
> 
> Actually, I don't think you can reach a valid conclusion by
> using any production vehicle as a basis for this discussion.

Excellent point, but not a race car either.  
> 
> Now, if you want to posit a THEORETICAL or EXPERIMENTAL car
> which doesn't have to live in the real world with passengers, cargo,
> soccer-mom trips, etc., I would accept the premise that THIS vehicle
> would be a possible test-bed for more than one drive system: FWD, RWD
> and AWD.  However, to test realistically, you would have to alter the
> static weight bias, braking system bias, and other characteristics as
> you changed drive configurations.  What one would end up with might
> be the best System A vs. B vs. C that an engineer could design, and
> that might be the most realistic way to prove this point.  (Of
> course, we totally leave out driver skill, a critically important
> factor.)

Remember the original arguement is that AWD is just not significantly in
the dry on regular cars(<350-400hp).  Would you give up your car based
on that? Neither would I.  Guess who said that?  I said that AWD IS
superior all of the time.  How do we prove it?  What is you null
hypothesis? 

> 
> That's the way I see it work out.  No one solution is best for
> everything.
> 
> Cheers to all.....
> 
> Al Powell, Ph.D.

-- 

Randall C. Markarian

1990 V8 Quattro
1996 Merc E320

Saint Louis, Missouri