"Joseph Gwinn" wrote in message
...
In article ,
"Ed Huntress" wrote:

"John" wrote in message
...
On Thu, 08 Apr 2010 07:29:27 -0700, Larry Jaques
wrote:

On Thu, 08 Apr 2010 08:20:07 -0600, the infamous Lewis Hartswick
scrawled the following:

I didn't read the whole tirade but Ralph Nadar
is/was an IDIOT. He lost all credibility when
he wrote " Unsafe at any Speed".
What a load of BS.

Yeah, he castrated GM while allowing the VW to go unpunished, despite
the fact that they had more problems than the Corvair, including the
extreme tendency for several to set themselves on fire almost as an
almost daily practice.

No that is not correct. Nader wrote Unsafe at any Speed, which was
pretty much a hatchet job to the extent that totally incorrect
statements were made and even a sketch of how a swing axle works was
deliberately drawn showing the outside wheel in a turn tipping inward
at the bottom, "tuck under" as Nader preferred to it when in fact it
does exactly the opposite, although if you do not understand how the
suspension works it might appear to be correct.

That's correct. I had an auto-mechanic friend in the 1970s who loved
Corvairs,
and he had experienced the tuck-under phenomena. The solution was to
install
the standard "sports package", which cost a few hundred dollars and
included
some kind of torsion or stabilizer bar between the front wheels.

The front stabilizer would limit oversteer (by inducing understeer), but it
didn't prevent jacking. For that, you needed the rear stabilizer bar, and/or
shorter rear springs to decamber the rear end.

I conquered it on my '63 with a combination of a stiff rear stabilizer and
the John Fitch decambering springs (negative 2-1/2 degrees.; it ate a set of
tires in a month or two, no kidding). But the stiff rear bar induced
oversteer. It was a tradeoff: I knew the rear end was coming around, but the
trade was that I could predict *when* it was coming around. When a
swing-axle car jacks, it's a violent transition, often with little warning.


He was of mixed mind on Unsafe at Any Speed. On the one hand, he
considered the
book to be wrong. On the other hand, it drove the cost of Corvairs down,
allowing him to buy more than one.


Ah, John, no. I hesitate to interfere with your trashing of Nader g,
but
he was correct. It was commonly called "jacking" among the sports car
fraternity. Anyone who drove an early VW, Corvair, Triumph Spitfire, or
box-stock Porsche 356 (including the original Speedster) will be glad to
relate some horror stories about it for you. d8-)

Some older chassis books can explain and illustrate the same thing. If
you
were actively driving sports cars around, say, 1965, you were very
familiar
with it.

I recall reading these explanations, but no longer recall the details. I
don't
recall that it was called "jacking", though. My friend didn't call it
that, if
I recall.

Joe Gwinn

There's a force couple which, all by itself, would make the outside wheel
tuck under into positive camber, every time you went around a corner. It's
partly offset by body roll, which makes the outer spring compress and
induces negative camber. The transition from one to the other can occur
suddenly and it can be severe.

The better your tires, the worse the problem. Radial tires killed swing
axles; with Michelins on a stock-suspension Corvair, you could jack the
ass-end of the car up in the air with the greatest of ease.

--
Ed Huntress