First of all thanks to all of you who sent your good wishes to me after my
middle age opus. I appreciate it very much. Someone once said that the
really important knowledge is the stuff you learn after you know it all. I
now understand and agree with it 100%. It is also a great line to use on a
13 year old who is convinced that my ignorance is what caused the dinosaurs
to suffer extinction.
About handling and tire pressure. I used to run the MGA's tire pressure
quite high all of the time. These were the pressures that kept the tires
at optimum contact (low as possible with no rolling under) so I figured
that they must be the best for everything. They also gave a rather
entertaining tail out cornering posture (the A is stock with no anti roll
bars so the rear roll stiffness causes it to give way first). On real
roads, however, I was finding that any bumps mid corner would set up a
harmonic in the car and the front tires would bounce. The A would then
plow until everything calmed down. Not exactly confidence inspiring
handling.
Now the A's shocks and rear suspension are pretty tired so this might
contribute but, for me, the answer was to reduce tire pressures. The
fronts may now give up a few hundrenths (sp?) of a G sooner on a smooth
track but they now stay on the road better in the real world and I am much
less likely to soil my shorts mid turn.
So, like Bill Spohn, Keith, and others have said- tuning is the key. All
the parts have to work together and optimising one thing may hurt something
else. Maybe if I had new shocks and expensive tires, and a car with more
torsional stiffness this wouldn't happen but I don't. I run a '61 MGA
with stock suspension, snow tires, and the body has never been off and, in
this case at least, running the "optimum" tire pressure is scary in the
real world.
Besides, playing with stuff like tire pressure, timing, and carb settings
(preferably with experience or guidance in a controlled environment yada
yada yada) is half the fun of owning these old cars. And when I do get a
chance to autocross, I may not be the fasted but with the A's tale hanging
out and me turning that steamer-sized steering wheel into the slide, I
doubt anyone else has a wider grin.
Regards,
Bill Eastman
61 MGA hanging out with a few friends in storage
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