I have kept the MGA exercised so far this week. Basically, if there is
somewhere to go with 2 or fewer people, the A gets the nod. It has, as
usual, performed flawlessly this week if we don't count the slipping
clutch, the oil leaks, and the puff of smoke on warm startup. This is her
last fling before a little maintenance break.
A long time ago, I wrote that the A had a slight problem with front tire
bounce on corners with high frequency bumps. This would result in a little
scuttle shake and momentary understeer usually followed by operator induced
over correction and oversteer. Since there were two high speed corners
like this between home and work, I had been getting quite a bit of practice
so the overcorrection is no longer too bad. Anyway, the problem seemed
worse last week. I figured that the left front shock had leaked down (it
had) so I included this in the pre BCW maintenance plan. When I checked
the tire pressures I found that they were up to 38 PSI due to the fact that
they were last adjusted in March when it was 30 F. Now I grew up with Road
and Track so I know that, in order to make a car handle, you crank up the
tire pressure. I used to run the MGB's pressures at 40 psi plus (I was 17
at the time). Under the obvious influence of a wild hair, I lowered the
tire pressure to 26 psi front and 28 psi back. this is closer to what the
factory recommended for bias tires when the car was new. I didn't expect
much since I could now shake the car and watch it oscillate on the now "too
soft" tires. The next day on the drive to work, the handling at street
speed was not noticeably degraded and, wonder of wonders, the tire bounce
was gone! I also filled the front shock but I had done this before without
getting rid of the bounce. Also, the car had developed a "lively" steering
wheel at around 60 mph. It wasn't really a shimmy- more of a vibration.
Reducing the tire pressures also eliminated this.
Before I have stated that the best tire pressure is the highest pressure
that you can stand from a ride perspective while still staying within sane
limits. Now I think maybe the ride/handling/tire pressure interaction is
more subtle than this- especially on our older, suboptimal designs.
I was driving the A last week quite a bit too but left it home due to dodgy
weather reports. I was planning to leave early for a child event but it
was canceled because of rain. At the end of the day a hailstorm came
through and now my daily driver looks someone attacked it with a ball peen
hammer. What a drag- every panel but the drivers side door is dinged. On
the plus side, after much discussion at work, it was theorized that the
hail damage may work like dimples on a golf ball and reduce wind resistance
so maybe my gas mileage will go up. The car goes into the shop on 16 June
and will be there for 2-3 weeks. So I need to get the A fixed quickly
since it will again be pressed into service.
Nancy just called and my parts are here. Yippee! Gotta get home!
Regards,
Bill Eastman
61 MGA top down and running strong
95 Acura Integra with custom aerodynamic dimples
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