coil spring front

HemiDenny said
HDK Single Lower Control Arm Torsion Bar Eliminator kit

Sorry, late to the party.

advantages of the HDK single chromoly tube LCA assembly are.....
a) eliminates the sloppy OEM torsion bar mechanism
b) utilizes a new (supplied) HDK thru lower pivot shaft to allow for a 100% bolt on double sheer rear support of the LCA
c) re-positions the coil over shock / spring mount slightly outward for spring to frame clearance.

the HDK upper shock mount / chromoly support hoop which has been used for over 20 years (with zero failures) also re-position the coil over shock / spring slightly further outward for coil spring clearance

combine the HDK chromoly tubular UCA assemblies (supplied but not pictured in the above link) and easily achieve up to 6 degrees positive caster without putting the UCA in any kind of a bind.
UCAs are available for all three widely used A body spindles....both drum and disc small upper ball joint found on most pre 72 A body's and the later larger upper ball joint model.

Thanks for looking,
Denny
HDK
304-939-0097
[email protected]

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!

Kern Dog said
You guys remember all those failures that were reported with the stock K members?
Yeah, me neither.

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.