Thanks to all who responded! I should dig through my library more. The old
"Triumph- Maintenance, Modification, and Tuning" by Mauclay has a whole
paragraph on setting Koni's. BTW, it is fully compress, engage slot, then
click left for softer, right for firmer. They really did the trick on the
front suspension: it handles 'a treat'.
We took Scrappy out to our desert practice area Saturday and she is running
great (never say that in front of the car). We picked up another 1/2 second
on our acceleration times with the new BFI equipped motor, and practice was
necessary.
'Practice' means heading out to our test road, where we have a measured mile,
low traffic, and a mile on either side for acceleration and deceleration. One
mile was measured and marked by Janet's dad, who is a surveyor: the location,
east of Palmdale (in the desert near Edwards AFB), is perfectly straight for
miles and lightly traveled. It's an hour to get out there: there are no long,
straight, lightly traveled roads anywhere near LA! Then, we run it back and
forth all day long.
First we run it at 50, hitting the traps at speed, to confirm the speedo
calibration. This is done with traffic cones and a stopwatch, and a speed
conversion chart. Our speedo was within .02 sec., good enough!
Next we do acceleration times: standing start, 0-10 through 0-50, in 10 mph
increments. We run each both directions to account for wind and gradient.
Then, I have to make sure I do it exactly the same way each time: if I am 1
second off I have to keep doing it until I am within .5 second consistency.
We figure .2 as human error and we can't do better than that. The
acceleration rate I use is much less than the car is capable of: that way, if
the start is on an uphill gradient, or at high altitude, I have reserve
power. I measure the rate of acceleration by counting a beat to the speedo
needle's rate of climb or descent. If you were flying, it's kind of like a
standard rate turn, or maintaining a climb/descent at exactly 500 fpm.
With no tach permitted on the race, I note my shift points and translate
those to speed: the exhaust note roughly hits a peak tone at 2700 rpm, and
this is what I use. This translates to 15, 27, and 40 mph for shift points,
and I will use those throughout the race. Overdrive is used for non timed
transit sections only: too complicated otherwise.
After we do acceleration times, we do 'at speed turns'. This simulates
slowing from any speed down to 15 mph, then back up to speed. We had
determined that 15 is the average speed for a 90 degree turn without a stop.
We do this from 20-15-20 all the way to 50-15-50.
Next we practice 'stop and go's'. This simulates approaching an intersection
at a given speed, coming to a full stop, then accelerating back up to that
speed. We have to do this 3 times in a mile to get a good average, then both
directions to account for wind and grade. The 50 & 45 mph runs are tricky:
getting all 3 in a mile is hard on the brakes, but you must accelerate and
decelerate at exactly the same rate each time, so you must judge your
distances well!
Janet does the math and the charts: she is only allowed the data that can fit
on a 3 x 5 card, which is laminated to her official ID tag (which we all have
to wear for 2 weeks). I have to do everything as close to the same way each
time as I can. And the car has to do it exactly the same way too: no missed
shifts, no coughs or stumbles. If our charts are good, the car runs well, we
do everything the same way each time, stay on course, and start on time, for
2 weeks and 3500 miles, we will do well!
Fortunately this practice session is also a good wring out for the car:
everything is working fine, including all of the modifications. I made notes
for a few more things: a pad for my right leg on the tranny tunnel, adjust
the steering wheel to the right so the spokes don't interfere with line of
sight to the speedo, things like that. Then it's on the trailer Saturday,
leaving Sunday for Atlanta!
History Channel will have a piece about Great Race on next week on "This Week
in History", June 11 & 18th (8 PM EST). We'll be crossing AZ and NM on the
11th, racing the 18th, so we'll miss it.
Steve & Janet Hedke
1957 TR3 "Team Scrappy"
Great Race #45
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