I managed to make out to the last MAC MOWOG-Series autocross of the season
with "Grace N. Violence", my Lotus Europa. I didn't bother putting the
headlights back in, as I am still planning on painting the car "real soon
now".
It is a lot easier to get coolant in now because there is a bleed screw atop
the new water pump. The car ran a bit rough as I started off for the
ballpark. I gave it an "Italian tune-up" on a deserted stretch of road and
it ran fine all day after that.
There was an interesting course laid out on the stadium parking lot. A
couple of places demanded that you plan ahead or you would find yourself on
the wrong side of the track. The most noticeable feature was a pin-turn
with lots of room around it.
MAC split the entrants into four groups. I was in group three, so I worked
the course as group one took their first set of three runs. It was still
pretty cold, and the cars were sliding around quite a bit on the asphalt.
It was clear and dry, so I figured it would warm up to 60F or so and
traction would improve somewhat.
On my first three runs, I realized that you can't keep 185-60-13 R1s in
baggies for five years and expect them to stick. ;-) I slewed around
quite a bit but managed to keep the front wheels in front and the car
between the cones. I only assassinated pylons on the second run. The timer
box announced a not-really-embarrassing time at the end of my third run. I
had hope for the next round.
It was warmer as the afternoon wore on, and times were dropping. I wondered
if my tires would take advantage of higher surface temperature. If they
did, I didn't know what to do about it. On my fourth and fifth runs, folks
told me the car looked great, but my times were a second slower than my
third run. My sixth run, I made two mistakes, including getting into an
understeer coming off the pin-turn and wound up even slower. So I had to
stand on my third run, which was not awful, but others did improve and I was
not among the fastest cars there.
I took Paul, our local Marcos enthusiast, for a fun run in a car as low as
his. A bit messy, but autocrossing Grace is always a hoot anyway. Even on
dodgy tires, the car always feels way faster than it is, and that
formula-car feel is different from what most folks are used to.
Now we come to our metallurgical lesson for the day. Rex, my Saturn
compatriot, wanted to see what the course looked like from a viewpoint lower
than that of his SC2. We strapped in and pulled up to the marshaling line.
I did my customary launch and BANG. The car didn't move. I switched off
the engine, turned to Rex and said, "Sorry, Rex. No fun run for you today.
I just broke the car." I suspected a U-joint. I remembered that Chuck had
just popped a nearly-new Spicer U-joint in his Datsun Z-car this season and
wondered if that was the deal. We got out of the car and I lifted the rear
deck lid. Nope. U-joints are fine. Left halfshaft was shattered. Not
bent. Not twisted. Shattered. The left-rear tire exhibited serious
negative camber since the halfshaft normally serves as the upper control
arm.
We pushed the car aside (lots of fun with the tire rubbing on the inner
fender panel) and continued fun runs whilst I fished out my motor-club card
and cellphone. Flatbedded the car back to my place. I was happy to see
that the truck had large nylon straps which held the car down via the tires.
Rex came over to help me push Grace back into the shop.
So what's the metallurgical lesson? I took a chance back in 1991 when I
stared rebuilding this car, and it took this many autocross launches for it
to catch up to me. One of the previous owners had a chrome fetish.
Pulleys. Rear cross-member. Valve-cover. Swirl pot. Yes, halfshafts. So
this winter I am going to do what I ought to have done in 1991: Take out
the hydrogen-embrittled chrome halfshafts and replace them with
plain-looking non-hydrogen-embrittled ones. I imagine the usual Lotus
suppliers will have them. If not, any driveshaft shop can make them up. It
is hardly rocket science, and the U-joints are not rare types.
For our British friends:
halfshaft = drive shaft
driveshaft = propeller shaft
U-joint = Hooke joint
Phil Ethier Saint Paul Minnesota USA
1970 Lotus Europa, 1992 Saturn SL2, 1986 Suburban, 1962 Triumph TR4 CT2846L
LOON, MAC pethier@isd.net http://www.mnautox.com/
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