handling, specifically the design of the rear suspension. It is called a
swing axle configuration. The independent rear suspension only had one
pivot point per axle (side) at the transaxle end of the axle shaft. The
axle end at the rear wheel was fixed to the trailing arm without
relative movement between the wheel and the axle. As the suspension
cycled through it's compression-rebound travel, the camber of the rear
wheel would change- in (compression) and out (rebound). As one went
around a sharp corner, like an hiway ramp, the forces and geometry of
the suspension coupled with body roll would put a significant upward
force on the outside axle pivot point (at the transaxle) and pop the
car on it's roof. GM was in court over more than several cases of
death, dismemberment, and injury to occupants. Many settled out of court
for undisclosed sums. Speeds were sometimes less that 35 mph. GM
completely solved that whole issue by modifying the suspension to
include two CV joints per axle. One at the transaxle, one at the swing
arm by the wheel so wheel camber is maintained.
It should be noted that this is the exact same rear suspension set up as
the Beetle until they too fixed it in '67 Ferdinand Porsche also
quietly made the same change from the 356 to the 911 also in '67 as I
recall.
I think this may have occurred in '67?? Not sure. Anyway, although the
later cars were corrected for this design, the damage was done and GM
killed the line in '69. Besides, they had an even better idea already
to go. The Vega. That open deck, aluminum block with essentially
chrome plated cylinder liners, coupled with an iron head was genius.
Also the first car with welded, rather than bolted on, hood, door and
trunk hinges.... Sweet.
All rear drive cars with the engine behind the rear axle, like the VW
and Porsche, have a learning curve to drive well at speed. You enter
the corner at speed and experience pretty good understeer with the
relatively light front end. The natural reaction is to lift. Do that
suddenly, or worse, hit the brakes (because you are not as slick a
driver as you think), and that motor out back becomes a nice pendulum
that snaps you into sever oversteer, bringing the novice driver directly
to the scene of the accident.
I've read Peter Egan's stuff for years. *Great* stuff. Excellent
writer. He's living my dream life..... Well, not the writing part.
Once I couldn't spell engineer. Now I are one.
Pete
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