How far do you want to go with this? Negative camber isn't the only
suspension modification that's a good idea, you also want to bring the
roll center upwards--the stock roll center is several feet under ground.
Making the upper arm shorter works okay--it raises the roll center a
little bit, and doesn't increase bump steer too much (though it will a
little--or course stiff springs and limited travel help here). Reversing
the fulcrum shaft is good because it raises the roll center more. The only
way I found to get the roll center anywhere close to the rear roll center
is to move the fulcrum pivot about a inch inboard, which means you have to
extend the upper arm a little bit to get clearance.
If you need a stock look, I'd reverse the fulcrum or even try to get a
more extreme offset if possible (I've heard they exist) and shorten the
upper arm a little bit. That's how Peyote is set up. It gets away with
having a fair amount of travel because it has a rack mounted higher up
than the standard setup on a TR3. If you get your ride height down to a
few inches clearance for the crossmember and a inch of downward travel
from loaded rest, it ought to handle pretty well. Much more and you'll
have a lively steering wheel over every crack and bump.
-----Original Message-----
From: Justin [mailto:jmwagner@greenheart.com]
Sent: Friday, October 12, 2001 2:00 PM
To: Jim Elbe
Cc: 'fot@autox.team.net'
Subject: Re: TR 4 NEGATIVE CAMBER
I just skimmed through research materials and found the following. (Some
doesn't apply to your specific request, but it still might be of interest
to
others.)
--Justin Wagner
"To reduce the positive camber you will need to make up new pivort plates
for
the bottom wishbone of the suspension....For each degree of positive
camber
reduction required, move the pivot bolt hole in the plate 0.170" outwards"
Tuning Standard Triumphs by David Vizard
"The front end would benefit form being able to adjust the camber, which
can be
accomplished by installing the lower control arms and brackets from the
later
TR 6 and welding them onto the TR3 frame at the same mounting points as
the
stock A-arms." "If that modification is too avant garde, then Day
suggests the
method racers in the 1950's and 1960's used to adjust the camber. 'The
old way
that we used to do it was heat the vertical link and eat with a hammer
until we
got our camber where we wanted and then let it cool,' he says." Vintage
Racing
British Sports Cars by Tery Jackson
A handy note for TR 4A owners...
"A good way to get 1/4 degree more negative camber it to reverse the upper
fulcrum shaft, on which the upper A-arms mount, as it is offset. This
shaft
usually rides with its bulging part to the outside. Reverse it so the
bulge is
inside and you'll increase negative camber" Grassroots Motorsports article
by
Tim Suddard
Jim Elbe wrote:
> What's the best way to get some on a TR 4 ??
> RMVR will not let you change mounting points or use non-standard
> components. I've read the book about heating and bending the uprights.
Is
> this still the preferred way to go ?? If so can someone recommend a
place
> that knows what they are doing ? Can the uprights only be sent to be
done ?
> Thanks in advance.
> Jim Elbe
> TR 4 #223
> P.S. Got my decals - pretty cool - thanks.
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