Glenn asked:
It seems like Roger Williams definitely recommends that I change the front
>crossmember, steering rack & pinion, and steering shaft to a RB model. BUT
>he also mentions that it is possible to use the existing crossmember in
>conjunction with a modified steering shaft. Is one way easier than the
>other? Is there a cost advantage? The only places I've seen advertise the
>modified steering shafts have been on the other side of the pond, and none
>listed the cost involved in such a change. I understand what is involved
>with the additional U Joints , etc. but don't have any idea of a price.
>
>Is there a general consensus of what is the easiest way to do the steering
>modifications of a chrome bumpered model?
Glenn....I very much doubt you will find a concensus on much of anything! I
completed my own conversion (early '74 B_GT,'62 Buick 215, "B" trans w/ OD,
8" Ford Rear) about 6 years ago when there was almost no information
available...I would have given almost anything to have a resource like this
list. Although not an engineer, I just adopted the attitude: " WHATEVER is
necessary is what must be done." Building the motor was the easy part.
Redesigning the steering system, using what was available was the hard part.
On to your question:
Here is what I did. A lot of thinking first. Every expert I asked had a
different way of doing everything. I lay under the cars for hours at a time
thinking the whole thing through. I lay awake at night wondering how I could
make stuff work. The motor complete with headers had to be in exactly the
place it would be. That, of course meant that the existing steering shaft
could not be there. With engine in place, I could use a broomstick (or
dowel) to determine where the real shaft HAD TO GO. Once you know for sure
what you are going to do, the engine must come out again to allow room to
work. Then some trial and error. I think I took 6 insertions before I
actually bolted my engine in place for the last time. Then, how to get one
there? First, I took a cutting wheel and cut off the steering rack mounts
flush with the crossmember, as it was obvious that they could not be there,
but must be relocated about 2 3/4+ in. lower. That also meant that the
original mounting angle had to be changed, which meant that another u-joint
would be called for. It seemed to me that the only location for another
u-joint was, very inconviently, inside the suspension crossmember! At the
other end, I determined that the original u-joint was just plain too big,
and again, in the wrong place in the longitudinal direction, and the hole
through the firewall needed to be moved in the lateral direction. The
shimming of the steering wheel shaft under the dash would have to place the
wheel lower by ~3/8"...pretty much necessitating a smaller diameter steering
wheel. It's hard to say exactly what order all these modifications were done
in. It was more like I started by seeing what must be done, and then making
gradual steps in that direction...it's always easier to cut a little more if
necessary than to try to put something back after you've cut it away. I
worked from ideas to "models" using wooden dowels, for example, as temporary
steering shaft, and using an elaborate system of vice-clamp pliers and
c-clamps to hold the rack mounts where I thought they needed to be, until I
would realize they needed to be moved, etc.....eventually I made a steering
shaft system that did everything it needed to do...at that point I started
welding. Yes, I was always scared to death that I would spend all this time
, effort and money to build a deathtrap. My very first welding job was to
attach the rack mounts to the crossmember! This made for an exciting first
few test drives in my completed car. I did have various friends with more
experience in these matters look closely at what I was doing...while
promising them I wouldn't sue them if I crashed and killed myself or someone
else. I'm sure there are countries that would not allow these sorts of
homemade engineering to be legal on the public roads.
To try to summarize, from one end to the other (and then back again...):
Steering rack mounts relocated about 2 3/4" down and tilted back ~30
degrees. I cut out the top and backside of the crossmember in order to place
a u-joint immediately where the steering shaft comes out of the rack. The
rack side of the joint was welded and the original splines on the other. Now
would be a good place to indicate I used rubber-bumper "B" u-joints at both
ends...they are much smaller. Since then I have seen even MUCH smaller
joints hardly bigger than the shaft itself...available through hot-rod
fabrication shops. Probably on every street corner in California, but
unobtainable in NC at the time.I cut ~1/2 inch off the end of the steering
wheel shaft just where it came through the bulkhead. This let me fit that
u-joint that much closer to the bulkshead and still use the splines. I did
weld the other side of that joint. The upper u=joint spent some time with a
grinding wheel to buy another 1'32" or so. Then I "moved" the 3 holes in the
bulkhead that the steering shaft passthrough plate is attached to the
bulkhead with so it could be shifted ~1/4" away from the header. Then I
reshimmed the connection where the steering wheel shaft hangs from the dash,
and replaced the large diameter original steering wheel with a beautiful, if
expensive, leCarre wheel of black leather and steel. When all worked as it
should, I welded "bridges" of 1/8" steel over the cut-outs in the
crossmember to strengthen it. I made this whole thing more difficult by
insisting on using the short, heavy-duty coil springs to get that raked low
look. All this produced the malady called "bump-steer", because the rack no
longer lived in the same plane as the steering arms connected to the front
wheels. They were already at their "compressed" limit (as if the suspension
had bottomed out...) even at rest...so there was nowhere for them to go when
a bump came along. To offset this I had a local racecar preparer heat the
steering arms and bend the ends down in "S"curve to meet the plane of the
rack better. In addition, I installed the negitive camber A-frame arms.
Does it work? Yes, it does very well. I have no looseness in the steering,
and it has lasted 11,000 mi. so far under all kinds of driving conditions.
Is it the best it could possibly be? I doubt it, but I don't race the car.
It seems safe and is fun to drive. Would I do it the same way? I don't think
so. What a tremendous amount of work. The use of a rubber-bumper crossmember
is surely easier, but wouldn't it also raise up the front of the car even
higher than original? And then, even if you put in the short springs, it
would only come down to standard. You have to have a clear vision of what
you want and the total determination to make metal do what you insist must
be done. If it's not fun to you, it probably isn't worth it any other way.
Total cost of my system was $45 for 2 used "76"B" steering shafts, and
probably hundreds of hours of blood and sweat.
Good luck with your project......ron howard
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