Sway Sway Sway

To improve the handling of the Imperial I’m upgrading the front sway bar to 1″ (from the factory 3/4″) and adding a rear sway bar. While going from 3/4″ to 1″ doesn’t sound like that big a change, the new bar is over three times stiffer than the old one! Torsional rigidity goes up as the fourth power of the radius, so small changes make a big difference.

I had ordered the new front sway bar over a year ago. Now that the front suspension is in place I can install it. The process is to remember where I stored it, unbox it and check all the pieces, read the minimal generic instructions, and test fit it.

And, of course, it doesn’t fit…Not a complete surprise; it is hard to get anything for an Imperial, and some tweaking to make it work is part of the “fun”. You have to periodically remind yourself that you are doing this for fun!

The mounting hardware puts the front of the sway bar right in the middle of the lower strut arms, which are a critical part of the suspension. I spent several hours trying multiple different ways of mounting the sway bar, but had interference no matter what I tried. Even when I dropped the front of the sway bar for clearance I still had problems with things hitting at some point during suspension travel.

After taking a break – of a week or so – I decided that the next step was to get the car off of the jackstands and onto its tires so that the suspension was in its normal position. Part of the problem was due to trying to fit things with the suspension drooping as far as possible.

With the car at a normal ride height, it was time to extend the front mounting hardware. The sway bar came with a 3/16″ mounting plate, another 3/16″ spacer plate to clear the bolt head, a bolt, a sleeve, and two suspension bushings.

Front sway bar mounting bracket as received

Lowering this involved getting a longer bolt and adding washers and other spacers. I kept adding spacers and trying to install the sway bar until it worked. I finally reached the point where I could install the sway bar and it didn’t hit anything through the entire suspension travel. Life is good!

Well, sort of good. I ended up with two 1/2″ nuts and six washers as spacers. While this worked, it looked like – and was! – a complete kludge.

Sway bar bracket with spacers

Nope, this wasn’t going back on the car! Time to head over the the WorcShop and use some of the equipment I mentioned in the previous post. If you have a machine shop, use it!

The bracket with spacers provided all of the dimensions I needed. I started off by cutting some 3/8″ steel plate to size and drilling holes for the base. Why 3/8″? Because it is overkill and I found a chunk of 3/8″ plate in the scrap bin. Next was to cut some 3/4″ diameter rod to length and drill it and tap it in the lathe. Finally, use the 300 amp shop welder to weld the rod to the plate. And voila – a custom sway bar mounting bracket!

Custom bracket

Mount everything on the car for one last trial fit:

Test fit on car

In this picture you can see the front bracket as well as the rear bracket – the rear bracket can be identified by the two yellowish grade8 bolts.

While the front brackets were fine, the sway bar was just a little too wide in the rear. I decided to space out the rear a little by replacing the 3/16″ mounting plates with 3/8″ mounting plates. Yes, I may enjoy playing in the machine shop just a little bit…