Anyone know if I absolutely need boxed control arms to install a rear sway bar? I bought a sway bar to add to my non-sway bar car. I came across a post somewhere that noted I needed boxed control arms.

I'm in the process of replacing the control arm bushings now so boxing them would be easier to do at this time if I'm going to even be bothered. I'm more concerned with if I need to do it. I know I probably should but wanted a second opinion before I waste the time and do it.

Thoughts on doing it yourself? I have a bunch of 16 ga steel (and there might even be some 15 gauge laying around) I can get from work so I'd just do it this weekend.

Thanks!

 

If you don't box the arms, then the sway bar will just warp the arm instead of keeping the car level.
Parts vendors sell inserts that are little more than bent pieces of 16ga (or so) steel. You want to add some metal inside the sway bar mounting holes so you don't collapse the arm.

 

Someone did that to mine. Bars squeezed in. Ruins control arms. Box em in while you can.

 

When I first did this, I cut some spacers from some 1/2" pipe and slipped the sway arm bolts through those as they went through the un-boxed arms. This prevents the arms from getting crushed as you torque the bolts. However, as was mentioned, the un-boxed arms are still flimsy compared to fully-boxed arms. This flexing reduces the effectiveness of the sway bar.


When I rebuilt my rear axle, I swapped the LCAs w/ some SSM lift bars which relocates the roll-center and improves traction by increasing the leverage the rear axle has to lift the car and transfer more weight to the rear tires on launch. The SSM lift bars are stout and have pre-drilled holes for the sway bar that won't crush.

 

Thanks Everyone... That's exactly what I was afraid of. I'll see if I can pull together some heavy metal and box 'em myself otherwise I'll grab a boxed/tubular set next week.

Other than the sway bars I'm keeping the suspension as stock as I can. I'm not opposed to tubular arms or urethane bushings I just don't see the need for a cruiser.

Hopefully I can sleeve the bolt and box the top with my mig welder!

 

The weld in pieces are pretty affordable


http://www.ebay.com/itm/Chevelle-Con...dYTxcv&vxp=mtr

 

might want to look at UMI rear control arms kit p/n UPI-401516B


Direct bolt in swap for oem arms - bar bolts right to them.

 

I am pretty sure UMI sells spacers for the non boxed control arms.
I really like Hellwig Pro-Touring rear sway bar, it can be used with any control arms, Unlike the factory design this bar does not bolt to the lower control arms, it bolts to the chassis and to the axle, and is much more effective. This allows the suspension to articulate freely resulting in better handling and ride quality.

 

Any idea if that setup would clear a W27 differential cover? Just curious since my car had what appears to be an original one bolted to the rear. My current setup is the UMI arms with a Summit Racing 1" rear bar, which bolts to the arms and does clear the cover.

 

I doubt it, it barely clears my LPW aluminum cover on my 12 bolt.

 

my current setup

 

What sway bar did you use to hook up to this kit?

 

I just read this...lol Nevermind

 

Thanks for all the great information. I didn't have time to wait for parts so I ended up making my own out of 16 ga sheet metal and some 1/2" schedule 40. I tack welded the pipe pieces in the control arm to prevent crushing and went the extra step and boxed the lower arms. If I could have waited it might have been easier to just buy a new set of loaded/boxed control arms and just bolt them in but it gave me a good excuse to pull the welder out! (not that I particularly need an excuse...LOL)

Thanks again! I have one control arm to finish (upper) and my suspension will be done...and all new!