I've done this. Once. No more.
There are a couple of advantages to using later model suspension
parts, though. The TR4-TR6 uprights (actually the lower trunnions)
have 3 deg caster built into them, giving the car a more "on center"
feel. The attaching points for the lower arms are positioned so that
you can put shims behind the brackets and shim the lower end in and
out, giving you adjustable camber. This is especially useful for
autocrossers and racers and folks who have lowered their cars for one
reason or another, because lowering the car changes the camber. There
is some more detail to the parts to use, but I'm trying to be as
simple as I know how.
The original lower arms can be used, but the uppers get changed to
the TR4-6 style.
Different brackets must be welded to the frame for attachment of the
lower a-arms. This can only be done after the existing main pivot
mounting studs are cut off, making this change irreversible. The
front surface of this new bracketry must be positioned so that the
pivot point after assembly is in the same location as those studs.,
and they must be positioned very precisely or you don't get the
proper range of adjustment. This is exceedingly difficult to do, it
takes some careful measurement and math, and to do it right a fixture
should be built so you get everything on straight.
This procedure has ben used on a couple of race cars that I know of,
but I don't recommend trying it unless you are a really accomplished
fabricator. And then, in my mind, the benefits are questionable.
The same adjustability can be accomplished by just switching to the
late model trunions and a-arms, and welding receivers for Heim joints
to the inner ends of the upper a-arms.
At 10:40 AM 9/21/2005, Woods, Ed wrote:
>List,
>
>Has anyone done this? What are the benefits? Is the TR3 frame modified to fit
>the TR6 lower wishbone arms or are the TR6 arms modified to fit the TR3 frame?
>Is it a permanent modification or can the car be returned to the original
>configuration easily.
>
>Ed Woods
uncle jack
|