Posting this reply to Ed Woods and Roger Bolick to the list. Roger
Bolicks domain "exact" is unknown to my mail server. But read on if
wishbones, fulcrum pins, camber and caster interests you.
Thanks Ed and Roger for your reply.
Roger wrote:
> Listen and learn...
all ears :-)
> The camber on the front tires is controlled by the shims at the bottom
> and the wishbone on the top.
>
> The old racers trick to induce MORE negative camber than anyone would want
> on the street is to "reverse" the wishbones. This can be done by pulling
> the bone and arms, rotating and attaching to the other side...
Wouldn't this also affect the caster? It appears that swapping the two
arms also would move the position of the upper ball joint backwards,
thus increasing the caster angle. Camber and caster in one fell swoop.
> As you will notice, the obviously correct installment where the wishbone
> is cut out for the shock is actually WRONG for a stock car.
>
> It goes so the mid portion almost touches the shock area.
> Look closely at the centerline of the pin to the centerline of the mouting
> holes. A couple of 1/1000 th's movement this high above the tire really
> moves things more than a couple of shims at the bottom.
Just found a drawing of the upper wishbone assembly in 'Owners Workshop
Manual - TR5 TR250 TR6', on page 78. From that drawing it is clear that
the centerline is different. At the same time, the drawing depicts the
bend the opposite of your recommendation, i.e. the fulcrum will bend
around the shock. However, the manual does not mention the proper way of
mounting the bracket, neither does the BL workshop manual. Maybe this is
the racing setup? If the assembly is drawn in top view it fits your
description above.
> Now for the real question, is all else on that car okay? i.e. was this
> reversed for a reason? No original car has ever had these removed...
> I would suspect the car was hit and either a mistake was made OR this
> was the only way you could get the crooked frame to line up... without
> fixing the damage properly.
Funny you should ask this. The guy doing the alignment on my car last
year claimed that it was an inch shorter on one side, and he had
problems getting the caster/camber values correct, which, by the way, he
never managed. The side with the fulcrum pin bent outwards towards the
shock is shimmed up to the max, which it should be according to theory.
However, I have noticed that the lower bushings (installed by me -
amateur! :-) aren't totally centered on the wisbone arms, and that could
be part of the reason why the car would appear longer on one side. These
will be replaced with SS/nylon bushings.
> Look at the bottom of the S-bend in the front of the frame, this should
> be nice smooth flat metal (unless some idiot used a bottle jack with
> nothing to spread the load) on both sides. Any hit to the frame will
> cause a wavy surface in this area that is impossible to get out....
I will check this out. The S-bend is parallell to the car? Have noticed
though that the frame member going between the front suspension areas is
not flat, but has acquired a concave shape in the lower part. The member
as such seems to be straight.
> I rebuild all mine with Nylatron bushings (TRF or Good) and poly everywhere
> else with all stock aprings, new sway bar and shock links and Apple HD levers.
Have got a stainles-steel/nylon kit for the front from Racetorations,
and in the rear I have hardened rubber from Rimmer which seems to hold
up well. The upper wishbone bushings have been replaced with SS/nylon.
> This with the new Michelin 205VR70-15 tires makes a CRISP handling car with
> a decent enough ride for the street. In particular I like the Nylatron
> rear bushings, of the whole mess, these are my biggest improvement)
New tires are on the shopping list. Right now I have a set of 205/65
Dunlops on it (which I got cheap and used from a friend), but will go up
to 70 profile to keep the original wheel diameter. I also have Spax all
the way around, set on 6 or 7 (14 clicks to choose from), which makes it
quite firm. The front springs are stock I believe, but the rear springs
appear to be stiffer than stock, but I have to count the coils before I
can say anything definite on that matter.
> For reference, I have rebuilt 6 cars in 8 years, all TR6's found dead.
BTW Roger, did you ever try and weld those telescopic shock brackets for
the rear, or is the project put on ice?
Thanks again to both of you
Lars
PS. Think I removed one of the fulcrum pins last year doing the front
bushings, then rubber, now nylon. Which pin I don't remember, but part
of the mess I'm in is probably due to that.
DPO = Dreaded Present Owner... Live and Learn...
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