It IS preferred to use the Miller-Falls (at the time) special tool, which I have seen in other places, from other providers, to remove and install the torsion bars. NO doubt about that.
By observation, any failure from the stress risers from the vice grip "marks" will not be immediate, by observation, but years later, if at all. I have no doubt that the issue of the stress risers is important, but might the issue of "rust" from exposed metal spots/areas be more important? As the earlier failures of '57 bars, many years later, from the lack of grease inside of the seals at the rear of the bars, was from "rust"?
With a torsion bar being, basically, an unwound coil spring, what makes the torsion bars have a different ride quality than a coil spring of the same ride rate and load capacity? Just curious,.
CBODY67
The failure won't be immediate, true. But you wanna depend on that? And how about when Grips were used to remove your bars in 1976?
A torsion bar is
almost an unwound coil spring, with a few differences:
1) A coil both twists AND bends, allowing for a number of better characteristics to be designed into the spring. More mathematics to work with!
2) A torsion bar has only a linear spring rate, whereas a coil can be designed to be complexly progressive. Progressive is a very good thing (except in politics) where the more the spring is compressed the harder it pushes back. A torsion bar....nope. One rate through it's range of twist, period.
3) A coil spring is generally easier to build into a vehicle, in that it only needs simple, rigid pockets at each end to hold it in place, instead of the fussy mechanisms of our lower control arms, pivots, bushings, adjuster dohicky, etc. [It's certainly easily adjustable for us, but I strongly doubt that feature was the intent of the original designers of the T-bar system. Some method was needed to preload the T spring, just like a coil spring needs a compressing tool to install it.]
So why the T-bars in our Mopars? With the coming of the unibody design in the late 50s, there was no rigid structure above the front wheels for a spring pocket. It was just flimsy sheetmetal there. The only reason for the T-bar was the packaging aspect of the sturdy trans crossmember and the K-frame. It's ingenious, but not "better" than coils.
I don't know this for a fact, but perhaps because the torsion bar works at the INSIDE of the control arm vs. a coil which is out there near the tire has something to do with the feel that our butt-o-meters perceive.
Incidentally, lots of other cars used variations of the T-bar, but usually laterally across the car like the F-bod cars and Bugs did. Incidentally, a sway bar is a torsion spring. Again, the design intent and packaging mandates a torsion bar for that application.
I'm pretty happy with the 1.15g skidpad numbers that
leaf springs provide for my Vette!