how to make a roll bar stiffer...

..and how to calculate how much stiffer before doing so?

this is for the front of my 95 Neon- there really isn't a common cheap and easy junkyard sway bar upgrade option for them.. but is there any way to calculate the stiffness gained by, say, welding a sleeve around it made out of a chunk of tubing?

moving the point where the links that tie it to the control arms really isn't an option since the links are only about 2" long and tie into a recess in the cast iron control arms and the bar itself sets into a recess in the bottom of the suspension crossmember, otherwise i'd think about making the arms on the bar shorter.

Are your sway bar bushings good? Some new ones can take a good bit of the play out. Though it wasn't enough for my car.

In reply to novaderrik:

I cant imagine how one would go about sleeving a U shaped swaybar in a way that would make it stiffer.

You could go with a modified car setup like from Schroeder. Predictable and tuneable. Or you could try fabricating your own, inspired by this straight torsion bar and bar arms design and perhaps sourced from junkyard swaybars...

Don't weld on a sway bar. Sway bars are heat treated, similar to a coil spring. Welding takes the heat treat right out of it.

Can you stack two of them?

Can you attach the swaybar to the strut instead? That will change the motion ratio from a mechanical disadvantage to nearly 1:1.

The small-chassis Audi guys do this.

Crud, now I can't remember if Neons have actual sway bar links, or if they do the thing where they clamp it to a bushing under the arm.

ncjay wrote: Don't weld on a sway bar. Sway bars are heat treated, similar to a coil spring. Welding takes the heat treat right out of it.

Was just gonna say this.

If you have to work with stock sway bars, your options are stiffer bushings, stacking two bars, or changing the motion ratio. Keep in mind you can attach a big billet clamp to the sway bar to make a new mounting point.

Larger diameter, shorter arms, more direct linkage.

Why do you want to increase under steer ?

Addco and pay $$$$$ for a custom bar???

In reply to novaderrik:

My autocross buddy and I both had 95 neons and we ran a custom setup using the before mentioned Schroeder style bars. The biggest part was getting the linkage figured out for the connection between lower control arm and the bar. I will try to dig around in my archives for photos but I think we had a spherical end link threaded into a bar of steel that was machined to clamp onto the swaybar splines.

Then you had to make custom sway bar mounts as the tabs couldn't handle the bigger bars so you needed to weld a stud or two onto the front cross member to accept the new mounts. The mounts were designed to have interchangeable shells similar to crankshaft bearings made of Delrin to match the bar diameter. The Delrin would move/deform over time but that became a maintenance thing.

The bar we found best to use was a little bit bigger than the bars out in the Neon aftermarket at the time. That would reduce the compression of the higher loaded front corner and thus retain enough camber to be effective.

Since you are out getting all of these custom parts made up. I would recommend also getting custom ball joints to lower the lower control arm from the knuckle and thus improve the camber change under compression. Actually I would think at this point in the age of the car you may be better off engineering a custom lower control arm and get away from the stock cast iron stuff. I have been wondering if the stock Mitsubishi Lancer Evolution 8/9 front lower control arms are even close in size and thus the front crossmember of the neon can be modified to fit. The answer of course is yes if you have a welder and can decently fab steel sheetmetal. Then you would need to modify a couple of Neon knuckles to fit the ball joint. Why? The Evo front lower arms have very nice bearings at all three points plus a good mount setup for swaybars. There are even readily available camber correction kit ball joints.

Zomby Woof wrote: Can you stack two of them?

Yeah. This.

iceracer wrote: Why do you want to increase under steer ?

Depends on the situation. If you are cornering on a front bumpstop or lifting a rear tire, more front bar will increase front grip, by reducing the effective wheel rate in the first instance (bumpstop means infinite rate) or reducing front camber loss in the second instance.

Shorten the effective length of the "arms" on the end. As previously mentioned, clamp the new mount on, don't weld it.

ISTR that ARB stiffness increases as the fourth power of the diameter.
So a mere 10% diameter increase would yield nearly 50% stiffer bar.

thanks for all the responses..

it was just something that i was thinking about last night while out in my 20 degree garage staring at the car.. i don't want to spend money on fixing the problems with the car- well, i wouldn't mind spending the money if i actually had any to spend on it.. just looking for junkyard/grassroots ways to make the car handle good and how to tune it in an endurance road race environment like Chumpcar. don't want to get into cutting and welding on the subframe or control arms because i consider them to the disposable parts that i want to be able to swap out with fresh junkyard parts.

changing the motion ratio of the bar really isn't an easy option thanks to the way they embedded it into not only the subframe, but also the control arms as well. i do have one idea that might work to make the stock bar tuneable and be easy to fabricate..

regarding the taller balljoint idea to lower the lower pivot point: that is accomplished with steering knuckles out of an early 90's Shadow, which also brings easily serviced wheel bearing/hub assemblies and bigger 11" brakes along with stronger axles along for the ride... car-part.com shows several junkyards in my area with knuckles for $20 each, so that's the way i'm gonna go with that..

ncjay wrote: Don't weld on a sway bar. Sway bars are heat treated, similar to a coil spring. Welding takes the heat treat right out of it.

what if i was to put it in the 1500 or so degree oven that we use at work to stress relieve steel after it's formed into a ring and flattened?

In reply to novaderrik:

Sweet I forgot that knuckle mod. Never ran in a class that would allow it so I never pursued it.

Good luck.

Oh one other idea we didn't pursue was figuring how to package the swaybar in front of the engine.

Heat treating anything properly is a bit more complicated than just heating it up. It's usually a multi step process. http://www.onallcylinders.com/2013/04/15/sway-bar-tech-heat-treating-and-why-its-important/

Advan046 wrote: Oh one other idea we didn't pursue was figuring how to package the swaybar in front of the engine.

there isn't anything really in front to bolt it to.

Sway bar mount brackets would be constructed to use the front lower control arm forward bolt position, where the wrench is.

Plus a third attachment point on the cross member either the damper mount bracket or most likely a new welded tab.

The sway bar would clear the oil pan but the "lever" arms for the bar would be rather short so the sway bar itself might be rather small. It would add a good bit of metal but if done right with Aluminum it could work and be light enough to be of value.

God, that was such a bad idea for sway bar mounting when they used it on the Omni/Horizon (L-body) and K-car platforms. At least they updated it a bit, but it is still a piss poor design.

Honestly, ditch that POS solution and adapt a real sway bar for it. Hint: look for a 924/944 in the salvage yard which uses an adapted Rabbit front suspension and mounts the sway bar ahead of the engine on the frame rails. Decent linkage with much less binding, but ultimately the linkage would have to be fabricated and don't be afraid to run the linkage below the arm. You can even get nicely built adjustable units for the 924/944, but they aren't cheap.

I feel like the quality of responses over here are better than the ones on neons.org.

I'm truly confused why nobody has mentioned the 22 mm front bar from the 03+ sxt/SE, the 24 mm bar from the srt4, or the 26 mm bar from the play cruiser get. They are all available in junkyards and on eBay. I paid $30 shipped for my SRT bar and loved it. The car also has a Progress hollow rear sway, I think it's 19 mm. Granted, mine is an 03 but one thing I've learned about Chrysler is that they make car parts like Legos. Your sway setup should be similar on the body and k frame. I'd recommend 2gn.org, is for later neons but I like it a lot more than neon.org; good knowledge base.

turboswede wrote: God, that was such a bad idea for sway bar mounting when they used it on the Omni/Horizon (L-body) and K-car platforms. At least they updated it a bit, but it is still a piss poor design. Honestly, ditch that POS solution and adapt a real sway bar for it. Hint: look for a 924/944 in the salvage yard which uses an adapted Rabbit front suspension and mounts the sway bar ahead of the engine on the frame rails. Decent linkage with much less binding, but ultimately the linkage would have to be fabricated and don't be afraid to run the linkage below the arm. You can even get nicely built adjustable units for the 924/944, but they aren't cheap.

Feels like the right answer but the car presents two difficulties.

First, on a Neon there isn't really anything to attach to forward of the subframe. There's "stuff" there but anything structural is pretty high up. The radiator just sits on a couple loosely folded sheets of thin gauge. Mounting the swaybar bushings on free-moving links, and then extremely short links to the struts to prevent it walking around very much, sounds like it might work.

Second, width is a problem, to package that engine and transmission, Chrysler felt that the transmission made an acceptable steering stop. Mounting under isn't very likely because the engine and trans sit lower than the subframe itself.