You can tighten up the “sloppy” torsion bar mechanism pretty easily if you box the factory LCA’s.
@Jim Lusk ’s video shows how he removes the slop when he rebuilds the LCA’s using readily available boxing plates. Tubular QA1 LCA’s also solve that issue.
I’ve run as much as +8° caster with tubular UCA’s without any binding, and currently run +6.5° with my SPC adjustable UCA’s from
@BergmanAutoCraft with plenty of adjustment to spare. So significant amounts of positive caster can also be achieved with a torsion bar system with the right parts.
No argument from me on the rest of it, like I said before, pros and cons to both systems and your HDK is a fine system that is well proven. Not much you can do about header clearance with the torsion bar set up!
That’s not entirely accurate. We all know that there have been LCA pivot tube failures, as well as cracked welds and mounts with the factory K’s. Heck the steering box mount on the V8 K I swapped into my Duster was cracked in two different places, allowing the steering box to move around when the steering wheel was turned back and forth.
Of course, those are issues you can fix by seam welding and reinforcing the stock K frame, which you can do for a lot less than a coil over conversion if you’ve got even amateur welding skills. I fully seam welded and reinforced mine with an old Millermatic 15, some 1/8” plate stock and some cardboard patterns.
And of course there are tubular replacement K frames for the torsion bar system too.
