[Shotimes] (OT) Snow & Ice Driving, was: Pontiac unveils SHO successor?

[Ron Porter]

There is a fallacy in your description, mainly with the sentences:

"So if you are PUSHING the car there are forces that are acting to
make it want to go sideways slightly, all it takes is to overcome the much
reduced friction and the car goes sideways.  If you PULL the car then there
are no forces acting to make it go sideways, in fact there are forces acting
to make it return to its straight-ahead path.

These are not true. In a perfect world, either pulling the car, or pushing
the car (FWD or RWD) will have the car move ahead perfectly straight. In the
real world, with torque forces, rubber bushings, uneven roads, etc, neither
FWD or RWD will pull or push the car straight.

And this gets to the core of the REAL problem with FWD. For years, I had
driven RWD cars on slippery, crowned roads with the rear end at a
20-30-degree angle to the front, and I merrily drove down the road. Not, on
the same road with FWD, with the tires start spinning.....YOU HAVE NO
STEERING!! When the front tires spin, no only do they start to slide
sideways due to (1) torque forces, (2) crown in the road, or (3) both of the
above. When this happens, you can sit there and crank the wheel around all
you want, it will have no effect.

I have been driving for 38 years, the overwhelming majority of it in snow
climates. Most with RWD cars, but two years of a FWD Riviera followed by a
Citation in the early '80s, then 15 years of SHO driving (ATX & MTX), along
with having RWD cars along with the SHO.

When I bought the '89 SHO, my wife bought the GT 5.0 5-speed, and for the
few winters in Lansing & Chicago when we had both cars, once  got decent
tires in the GT, I would take that out in heavy snow more often than the
SHO.

Overall, give me RWD with posi and good tires over any FWD car any day. 

I now own AWD, which will make the above issue a moot point going forward!!

Ron Porter

-----Original Message-----
From: shotimes-admin@autox.team.net [mailto:shotimes-admin@autox.team.net]
On Behalf Of bjshov8
Sent: Wednesday, November 03, 2004 9:49 PM
To: shotimes@autox.team.net
Subject: Re: [Shotimes] Pontiac unveils SHO successor?


The original discussion involved bad weather conditions.  A vehicle on flat
dry pavement with the wheels turned straight ahead requires very little
force to move it directly forwards or directly backwards, but due to tire
traction requires a lot of force to move it sideways.  Now on snow or ice or
to a lesser extent on wet pavement, it requires less force to move it
sideways.  So if you are PUSHING the car there are forces that are acting to
make it want to go sideways slightly, all it takes is to overcome the much
reduced friction and the car goes sideways.  If you PULL the car then there
are no forces acting to make it go sideways, in fact there are forces acting
to make it return to its straight-ahead path.

We have to keep this in mind when designing buildings- you don't want
certain parts of your buildings wanting to go sideways when you push on
them.

Interestingly enough in a RWD car the caster setting of the front end has
similar behavior.  If your caster setting is one way then the steering
naturally wants to return to the straight-ahead position but if your caster
setting is the other way then the steering is unstable and wants to turn one
way or the other.

> Easier to push than pull ???  I want to see you Push a log chain, any
questions ??
>
> Ron Porter <ronporter@prodigy.net> wrote:Not a relevant example. Pencils
don't have wheels or steering.
>
> Try a toy car. No easier to push or pull it.
>
> Better yet, try this. Let's say you are driving with someone, and your car
> dies in the middle lane. Do you push it off the road, or do you pull it
off
> the road?
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