No, not the Britcars list. Another list.
One of the only good things about taking a break from racing is that
it frees up my time and money to a tremendous degree. In addition to
being able to spend time with my family instead of with a tribe of
hirsute, sleep-deprived, grease-smeared fellow addicts on weekends
and evenings, I've had a little spare cash to do things like buy clothes
(something I don't think I'd done since 1990, if you don't count sweat-
shirts and Nomex) and the occasional paperback book (Carroll Smith's
Tune to Win doesn't count).
More to the point, it's also given me the budgetary freedom to make the
green MGB my number-one car. That is, while I was building the race
car and trying to get it around (or for that matter, trying to get it
TO) Sears Point and Laguna Seca, the green car had to settle for regular
oil changes and a lot of promises. Yes, dear, I'll do the wire wheels
one day soon. Yes, dear, I'll replace the missing nut in the starter
solenoid. Yes, dear... I was beginning to sound like Dagwood telling
Blondie when he'd fix the roof.
By the middle of June this year, I had paid off most of my pressing
debts from racing last year, and my savings plan came due. So it was
time to make a list of what annoyed me about The Green Car and decide
how to go about fixing the worst of those annoyances.
I managed to get it down to four things (having already fixed the
worst one on the list, the leaking head gasket): the severe wire
wheel judder at freeway speeds, the frighteningly loose rear end,
the off-throttle stumble between 2000 and 3000 RPM, and the exhaust
leak. Contained within those annoyances were a few other problems,
such as the fact that the tires on my wire wheels were probably
purchased while the car was still under warranty, but this list
contains the top irritants of MG ownership for me. (Let's face it:
unless you restore the car and seal it in a bag, any 20-year-old
British sports car is going to have a never-ending list of things
that need tinkering. That's part of their charm, right?)
Well, I've ordered the parts to fix the first, I've got the parts
to fix the last and the second, and this morning I fixed the third.
In that sequence:
I broke down and ordered the centre-lock Minilite replicas that
the usual places have been advertising lately. Moss Motors has
been running a sale with a sliding discount rate, starting at 8%
(I think) and topping out at 15% if you buy more than $500 worth
of stuff. Well, four of these alloy wheels easily put me into
that category. But they're on the way now. They're almost exact
replicas of the wheels used on the very last factory-sponsored
racing MG, for what that's worth, a 1968 or '69 lightweight MGC-GT
used in that year's (whichever it was) Targa Florio. They look
like the regular Minilites from the rim inward to the center section,
but the area where you'd install the lug bolts is replaced by a
polished steel disc held to the aluminum with eight studs and eight
shiny nuts, and the splines are cut in this steel section. They
are going to look unbelievably cool with the early winged knock-offs
I've got on the car now, and their extra width (5.5" compared to
the wires' 4.5") will let me run some modern tires without fear
of excessive sidewall flex.
The rear end is next. When I go over bumps in the road, the rear
wheels move an inch or so in the direction of the perturbation of
the vertex normal (in bump-mapping terms). It's exciting. So
I counted... there are seven places on each spring that can induce
this kind of uneven handling. The forward spring eye is one of
the worst, since it's one of the stiffest pieces; it's a rubber and
steel bushing that's fast bolted to the chassis, but when the
rubber goes, you get this kind of stochastic four-wheel steering
effect. Not fun. Then there are the spring mounting pads, one
above and one under the leaf springs, flattish pieces of rubber
designed to cushion the passengers from some of the axle's shocks.
Last are the four rear shackle bushings, little mushrooms of rubber
that hold the spring to the shackle and the shackle to the frame.
(Oh, in answer to the question -- yes, I checked the U-bolt nuts,
and they're tight as can be. In fact, I'm a little worried that
they'll be hard to remove because they look fairly solidly rusted
onto the bolts.)
Well, I've got new stock bushings for the front, and new Nylatron
replacements for the rest. Nylatron -- contrary to Kim's comment,
"Weren't they the evil robots that Dr. Who has to fight?" -- is a
trick space-age substance, made of nylon impregnated with molybdenum
disulfide. The idea is that it permits movement only in the intended
direction; the random jiggling that's going on now should be completely
eliminated. Based on the way the car's been handling, I think I'll
do the bushings this weekend.
The exhaust leak... I'm wimping out on that, I'll pay to have it
done. I don't mind working on the engine, and I don't even mind
working on the back axle because it's easy to get to. But the
exhaust leak is all coming from the missing doughnuts between the
header and the downpipe. I've got the doughnuts, I just hate
trying to get to those nuts. I'll pay someone to put the car up
on a hoist and use air tools.
But the best part is the throttle response fix. I'd first noticed
the problem with throttle response (really, just a flutter when
you'd open the throttle anywhere between 2000 and 3000 RPM, and
a tiny hesitation before the car caught) when I took the distributor
out last fall to dismantle, inspect, and rebuild it.
At that time, I had used my newly purchased timing light to
verify that my timing was right where the book said it should
be, at 10 degrees BTDC. Sure enough, the marks lined up just
spot on. Charlie Rockwell's analyzer said the same thing, in
fact pointed to rock-steady timing on all four sparks. It
looked like a new distributor to the computer. And even the
smog test in April showed that I was still dead on at 10 BTDC.
So I read through the Bentley manual last night and noticed an
astounding phrase in the section on Ignition (proving that you
should read the WHOLE effing manual, not just the data sheets).
If you use stroboscopic timing, you must remove the vacuum advance
mechanism from the distributor or the timing will be retarded.
Of course, of the three of us who checked timing, nobody yanked
the vacuum line.
Unfortunately, it was coming along towards eleven o'clock when I
learned this, and out of consideration for my neighbors I managed
to put off tweaking the car till just before breakfast. So this
morning I walked out to the garage, raised the hood, and wondered...
Now, I could run the car to warm it up so that I could drop it off
the choke and get it to the correct idle speed before I hooked up
the timing light. That'd be the scientific way to do it.
Or I could just eyeball it to see if it really made a difference.
That'd be little short of superstition and black magic.
MGs being somewhat mediaeval in design and implementation, I decided
to go with superstition and black magic -- trial by combat in the finest
tradition of Sir Wilfred of Ivanhoe. I grabbed my good 7/16" S-K wrench
and told the car that I'd let it decide: if I dropped the wrench while
reaching to undo the clamp, I'd take it as a sign that I should do the
right thing and use the timing light on a warm engine. Otherwise, if
I didn't drop the wrench, I'd take it as a sign that I was on the right
track and I'd continue with my task.
I didn't drop the wrench. More to the point, on the few times that
it would slip in my fingers as I shifted to get purchase on the nut,
the wrench would always carefully, as if directed by some magnetic
force, slide back into my grip.
I dialed the distributor -- first a little too far, then back to just
the width of the coil wire and then some more advanced than it had been.
I topped up the dashpots, checked the coolant, noted that the oil was
just to the top of the MAX line when I'd removed the dipstick to get to
the distributor, and test-fired the car.
Well, it ran, anyway. Hey, it sounds good... still cold, and the
richness was masking the response problem -- in fact, for a few
months I'd been able to ignore the problem by dialing the carbs a
couple of flats rich, but that's not the right way to solve it.
I went in to breakfast and decided to see what happened on the
way to work.
I was able to put the choke in blocks earlier than usual; even when
cold I had more response. And by the time the car had warmed up, it
was nothing short of amazing. Probably not more than a 2 to 3 bhp
improvement all told, but I'd clearly been wrong before (the book
seems to lead me to believe that I was betwen 6 and 10 degrees
retarded). Everything about the car's engine is better: it even
sounds better at idle now, in spite of the exhaust leak.
Next stop: Babe's Lightning Mufflers, then the Auto Parts Club for
one of their $55 floor jacks so I can fix the rear end. And in a
week or two, I'll pick up the wheels and get to decide what tires
to put on them...
--Scott
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