I haven't used any Hotchkis upgrades, but I did upgrade to PST torsion bars (1.03"). I wanted to stiffen things up a little in the front end. I also upgraded to polyurethane bushings, upper and lower ball joints, etc.
In the back, I replaced all the leaf spring bushings, and had
On my 67 Belvedere, I went with a Hellwig 1 3/8” hollow sway bar, Firm Feel 1” torsion bars, ESPO HD leafs and Hotchkis/Fox shocks. Here are the reasons why I chose the mish-mash of parts. Originally I ordered a Hotchkis sway bar but when it showed up, the wrong bar was packaged inside. Also, their frame brackets and end link brackets require welding. I saw that AndyF liked the Hellwig mounting brackets so that was enough of a recommendation for me. The Hellwig kit is very nice. The Firm Feel bars had a wheel rate of under 200in/lbs so it still rides nice. The Hotchkis shocks I got for a very good price from FABO. All of this replaced pretty low mileage small block suspension parts and they made a huge difference. I also added a Dr Diff disc brake kit. Next will be a Firm Feel 20:1 manual steering box.
Wow. Great info. Thanks much