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Michael Shields asked on Sat, 18 Jan 1997 10:19:11 +0000 (GMT)
Subject: So what's good about FWD?
Since all the racers are delurked this might be a good time to ask 

I can understand the advantages of RWD over AWD -- predictability,
low weight, low cost, less complexity (= more reliability, quicker
to market).  And I can understand the advantages of AWD over RWD when
you have more horsepower than traction.

But I cannot figure out why anyone would build a FWD car.  You get the
design constraints of a wheel with both steering and engine attached 
it, along with all the disadvantages of 2WD, and you also get weight
transfer to work against you.  There must be some reason everyone is
making FWD cars.

About the only advantage I've heard is that FWD cars are better than
RWD in a low-traction environment and the only reason I can think of
for that is that FWD cars always have nose-heavy weight distributions.
Even if you want a weight balance other than 50-50 (and it doesn't 
to me that you would), wouldn't a rear-engine rear-drive car be the 
to go?  Why aren't Camrys built like that?

I just don't see any advantage to having a front-engine front-drive 
*no matter what* your priorities are.  But most cars on the road are
built like that.  Including non-Quattro Audis.  What am I missing?
- -- 

As the owner of a turbo 1966 Corvair and various now defunct VWs, my 
observation is that both with snow tires on all 4 wheels do very well 
in low traction conditions.  I could plow with the Corvair if the snow 
was fluffy enough.  However, at high speeds, (70 on the interstates in 
a few inches more or less of snow) the Corvair was a bigger handful to 
keep under control.  One had to be on top of the car all the time.  
Most car buyers will be safer with FWD IMHO.  (N.B.  I am _NOT_ a 
Naderite.)  With RWD, rear engine (as opposed to mid engine), there is 
a high polar moment of inertia relative to the steering.  If one makes 
an error in low traction conditions, such as the common mistake of 
trying to brake and steer at once, the car can swap ends.  (BTDT)  In 
dry conditions, with optimal summer tires and optimal suspension 
geometry, the steering response can be adjusted for understeer or 
oversteer as desired.  I suspect a Corvair can outcorner (without 
defining this hotly debated term) a theoretical equivalent FWD car 
with the same HP/wt ratio and wt/tire size  ratio.

I haven't driven my Corvair since 1972, but the improvement my 90Q 
made over my ex 1984 Scirocco was quite noticable.  Maybe we will all 
still be around when I can compare the Corvair to the Audi.

***                 ...Kirby    (Kirby A. Smith)                 ***
***              ksmith1@mailgw.sanders.lockheed.com             ***
***              [=]   kirby.a.smith@lmco.com                    ***
***  Opinions expressed herein are entirely those of the author. ***