12:05 Garage- ’70 Duster build

DionR said

I like it! BTW, I don't think SendCutSend can bend 3/8" plate. If you had planned to have them bend it for you.

I assume the calculations take into account the length of the arm?

What size was the original sway bar? Could just be the angle, but looks dinky and with a fairly long arm to boot.

Click to expand...

I would have had them cut only, but added a slice about 1/8-3/16" all the across leaving 1/4" on each side so I could have a reference to bend. Then just weld the slice up. Go back and look at the saddles for the tube. That was the same idea. On these, I cut about halfway through the flat bar, then heated it, bent it, then welded. It makes for a clean bend and right where I want it. Also, I'm bending steel in a bench vice, I don't have a press brake.

Since I have nearly the same wheel rate as I used to with the torsion bars, I used the Hotchkis sway bar as a place to start. Using this calculator --> Sway Bar Rate Calculator - Addco I was able to determine the rate of the Hotchkis bar. Then I worked backwards using common tubing diameter and thicknesses. I ended up with the same diameter and thickness as the Hotchkis bar. It is currently setup in the hole that is damn near the same rate as the Hotchkis bar (746lb/in) and I have a hole 3/4" in both directions. This equates to almost 100lb/in more on the short side and about 80lb/in less on the looser side.

The bar Denny supplies is a 1" solid. The spring rate on it is around 250lb/in. So this is a substantial change. Remember, Denny didn't design his kit to be full on pro touring, road race setup. He has offered to make me a bar, but I wanted to try this.