Steve,
This thread seems to raise more questions than it answers. For example:
"When it came to the steering, then he chose a rack mounted to the front
suspension cross member to get around the block, but the connecting rods
from the rack to the steering arms were straight, and would not connect to
the steering arms, which were much further back."
and
"Carroll (known for his driving and marketing skills, not his engineering
expertise) told George to just bend the arms back so they would fit. "But
the Ackerman Angle will be all screwed up", George advised (as he tells
it)."
Just to be clear, bending the "connecting rods" [i.e., tie rods] has no
effect on Ackerman geometry. George's statement in this regard is somewhat
ambiguous, so I give him the benefit of the doubt; what he probably meant
was to consider moving the engine and rack, not just bend the tie rods.
But, I'm also skeptical about whether the tie rods really needed to be bent,
unless the rack was even farther forward than the production version. I and
many others have installed straight tie rods with only a small difference in
geometry. I believe the only issue is whether the range of motion of the tie
rod in the rack is sufficient for all driving conditions. It certainly has
the distinct disadvantage of weakening the tie rod.
Also, I'm confused by Bill's statement that he replaced the "tie rods". Why
would anyone need to replace the tie rods? Assuming he actually did, for
some unusual reason, replace the tie rods, then I'm inclined to believe that
they actually were from an MG and were straight. Quoting from Bill's book:
" 'Steering was the next big hang-up.' Ian says, 'but we knew what we wanted
to do. Design was not the problem. Our big problem was finding the right
parts so, as you can imagine, much of the parts selection was done by
eyeball fitting. If it looked like it would fit, Shelby's men would try it.
The MGA rack and pinion steering came closest to doing the job with without
extensive modification. This is what they put into the white prototype.
Because a major point was to make the steering completely safe, we wanted to
use only production parts' Ian explains." Taken literally, this statement
means the MGA rack was used "without extensive modification"; i.e., with the
stock tie rods.
And, BTW, Bill's book also includes this statement: "Later reports disclose
that engineering and construction done by Shelby American were so
comprehensive and painstaking that only two significant changes (throttle
linkage and shock absorber setting) were made after testing by Rootes
factory engineers prior to approval for production." I'm pretty sure a few
more changes were made - even beyond bending the tie rods.
Bob
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