Doane Spencer engineered the quick ratio rack for the #55 car as the result
of a race at Candlestick Park. Jim Adams lost control the car with the
steering jammed at full opposite lock, and went off the track and slammed
into one of those moveable concrete walls with hay bales in front. Doane
determined that the lock-up occurred because the stock rack had bent and
jammed up everything internally.
So he built a new one. Actually, as Bill Martin reported, he built 3 of
them. One was put in the car, and the other two, which were not totally
assembled, were kept as spares. I don't think they were ever used, and in
later years while Doane was still at Hollywood Sports Cars, I bought one of
these racks from him for $100. Ken Mattice bought the other one from
Schroder Engineering, a company who did the machining work for Doane (they
also did the LAT 70 wheels.) These were complete assemblies, and included
the housings, gears, special bearings and everything.
As Bill Martin observed, Doane's design was a really trick arrangement, and
it became one of his most closely guarded secrets. The rack bar was
machined from very high-grade steel, and the thick teeth were face-cut at a
90-degree angle. Much thicker than a stock unit, Doane's bar completely
filled the stock housing, and was longer than stock. In fact, the ends of
the rack extended out well beyond the ends of the housing, protruding clear
out into the rubber boots. Doane didn't want anyone snooping around the
front end of the car because if they looked at the boots they might
discover the extended rack and recognize that the steering had been altered
(what an understatement!) He often said something like, "I wasn't about to
show all those dumbies how to set up a Tiger!"
About the only way you could might spot something different about Doane's
rack was if you happened to notice the pinion gear, which protruded from
the housing at a 90-degree angle through an eccentric sintered-bronze
bushing. The outside of the bushing was splined and fit into an insert in
the aluminum end-piece of the housing, thus allowing adjustment of the
pinion lash, one spline at a time.
Of course, Doane used shorter, straight tie rods as part of his front-end
geometry, but I didn't know that when I tried to install his rack in my
street Tiger. Using my stock tie rods on the extra-long rack bar, I had a
whopping amount of toe-out. And the steering response was so quick a sneeze
would result in a lane change. So Doane's unit was not practical for me,
and I traded to a local Tiger racer for a stock rack and some cash. Andy
Heaton now owns that local race car, but when he got it Doane's steering
was long gone. Ken's rack went to his friend Bill Miller (long-time
conservator of the #55 car), who still has it in his green street Tiger.
Years ago, Mattice and Miller marketed quick-steer rack and pinion kits
which, according to Ken, were a copy of Doane's. These numbered kits were
produced by Mitchell Engineering, and there were 16 of them. Ken says that
later a second batch was made in England, but these had helical cut gears
and were pretty much direct replacements for stock Tiger units. Tom Hall
acquired the remains of that inventory and may still have a few units left.
I'm not familiar with the San Diego quick-steer components reported by Dr.
Palmer, but I doubt that they were true copies of Doane's stuff.
Dick Barker
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Bill Martin wrote:
"The Spencer quick rack is still with the car, from my research I learned
that Doane had three racks made up. We only go one with the car and it is
totally trick." (snip)
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Bob Palmer wrote:
"Back in the mid to late 70's time frame we had a very active Tiger club
here in San Diego. Among our activities was to have a local firm
remanufacture the Doane Spencer quick ratio rack." (snip)
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