>I'm curious about anyone's experience with replacing/updating the single
>transverse "swing spring" in the back; I'd like to go to independent
>coils, preferably connected to the frame. Are there any such conversions
>out there?
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Replacing the spring is a pretty simple straightforward job. Jack up the
rear, remove the plate covering the spring mounting studs/nuts. Unbolt,
remove and replace the spring. Altering the suspension is another matter.
The problem with going to coil overs in the rear would be that the spring
is also the upper "A-arm" as it were, but this design does much more. I
had thought about doing something similar, by making a bracket that bolted
to the diff. where the spring mounts, and then fabricating a couple of
upper control arms that connected to this bracket, but opted instead to use
the setup from the GT6+ since everything was already engineered.
Besides, with coil overs the way I described earlier you would still have a
swing axle rear suspension, but without the benefit of the swing spring.
This would have required a camber compensator of some type to correct the
high roll stiffness you just re-created by eliminating the existing spring
design. There is nothing intrinsically wrong with a leaf spring. It has
somehow received a less than glamorous reputation (and I feel undeserved,
as this particular design is a remarkably simple and effective independent
rear suspension for what it is), but all springs are torsional devices, and
function basically the same way. They just go about it formed in different
configurations. The different designs have their strengths and weakness,
but most designs are chosen over another, usually for packaging or
manufacturing reasons so to speak, not because one is a better spring than
the other. It was probably as much work (or possibly even more) to go to
the GT6 swap, but parts are *readily* available and I have a truly
independent rear suspension, (which I feel is worth the addled work and
obviously Triumph did too, or they wouldn't have gone to the extra expense
of fitting it to the car) with the geometry already worked out.
Barry Schwartz (San Diego) bschwart@pacbell.net
72 PI, V6 Spitfire (daily driver)
70 GT6+ (when I don't drive the Spit)
70 Spitfire (long term project)
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