Rich, and Group. The R&P kit from Dale A uses a MG Midget R&P, MGB steering
arms, etc. The stress on the fulcrum pin, comes when the wheel is turned, and
especially when the car is backed up with the wheel at full turn.
You will note this as the tires will scrub, and their may be a chattering in
the steering wheel, if backing up too fast.
Tom Hall has documented all of this for years, in excellent articles.
The problem with the suspension is the Ackerman Angle, which is reversed in the
Tiger, from normal suspension geometry.
The Dale A kit corrects most of the Ackerman Angle problem, and the Midget R&P,
also has a much larger turning radius than the Tiger stock R&P, so the stress
of the tight turn on the fulcrum pin is not as server.
Personally, I would not drive any 35 years old car, of any make, unless I knew
all of the suspension parts were rebuilt, and in good condition. It's not that
hard, or expensive, and the information's has been out there for years.
See the Tiger United site, or STOA site.
Driving on 35 year old tires, suspension, and with brakes that have not been
rebuilt is just not that smart. Put your money on the safely items, then the
chrome, wheels, and paint.
Larry
Rich Atherton wrote:
> Delrin is a relatively soft slick plastic material. I made my own
> bushing for my Alpine almost 25 years ago. I never really had a chance to
> test them out very much as the motor let go shortly after that suspension
> rebuild.
>
> It's funny too that even though the suspensions between the Tiger and the
> Alpine are identical other than spring rate, that only the Tigers seem to
> break the pins. The truth to the breakage I think can be directly related
> to modern technology, and the very poor steering geometry the Tiger has when
> making turns. Something the Alpine did not suffer from. Certianly the
> harder, less forgiving plastic bushings put more of a shock load into the
> car through the pins than the stock rubber ones do. No question about it.
> Delrin less so than Polyurathane one which are even harder, but more
> popular. Now take that shock load, with the unforgiving bushing, and now
> add the Tigers scrubbing forces of bad geometry, through modern
> technologically superior tires that are far stickiers than those Bias ply
> tires the car was designed with, and you have a combination that is beyond
> the cabailities of the fulcrum pins physical design can handle, regardless
> of material. it is inherant in the design of the pin itself.. It can't be
> made thick enough, or large enough and still fit the suspensions... As I
> remember reading not so long ago....Haven't most tigers snapped pins while
> backing out of their driveway and turning the wheel there by inducing some
> slow speed, yet HUGE loads on those pins..??
>
> I recently saw a gentalman here in Edmonds Washington, who built a v-8
> Alpine..Was never meant to be a tiger. Still used a modern 5.0, and of
> course had to change the steering... he desinged a rack and brackets that
> fit under the engine, and retained the Alpines steering geometry, or at
> least dam close to it. I saw it lock to lock, and there was no scrubbing..
> THIS is what is needed to make them safe.. Just my opinion...
>
> Rich..
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