Keith, don't read this.....

OK. Keith is now a Challenge Concourse judge, but that has nothing to do with my current need. I'm building a Challenge Miata and I need a cheap front swaybar solution. I'll be hitting the local pick-n-pull yards looking for something that in an ideal world, would bolt in. Since this is on a par with winning the Powerball I probably need some other answer. I may be able to find something close enough to cut and weld, I think. Has anyone cut the ends off an OEM bar (for any vehicle) and welded new tabs on? I'd slot the end and weld in a chunk of flat bar with multiple holes for the end links, at least that's my thought.

The steel would lose its tempering from the heat.

Would it be easier to run two sway bars with some fabricated brackets and bushings?

Woody answered it, try doubled-up sway bars. You can clamp or bond new end-links on, but not weld.

Weld a piece of angle iron to the stock bar? I've seen this done with success before.

This is someone else writing from Keith's account

I've shortened sway bar arms in the past. That part doesn't flex so the change in temper doesn't seem to be a problem. In fact, if you have a 1.6 chassis, grab a 1.8 front bar and shorten the arms a bit. It's a thicker bar.

Interchange - the Factory Five Roadster uses the same bar as a 1.6 Miata. I know this because we sell upgraded bars to FF But they're hard to find in junkyards.

I haven't done it to a Miata (yet), but I have stacked 2 stock bars on other cars with good results.

thing is that heat destroys the temper and would also introduce stress risers. So you are basically playing with making the bar deform without springing back, or, breaking. Maybe not right away, but much much sooner than the original piece, or one made properly.

There is a way of doing it, but it would involve heating it up (something like the 600*F range, depends on grade of steel) and holding it there for a specific amount of time.

Easier to get two stock ones and stack them. It will last longer.

if you want to dive further... http://www.metalsmith.org/pub/mtlsmith/V21.2/Springs.htm should get you started on concepts.

(I have a Mat-Sci Engineering degree, but I havent messed with this stuff directly or recently, only in theory while in school and some reading since)

I did double sway bars on our $2013 Challenge car. It took about 10 hours of fiddling to get it to work right. Sometimes there really isn't much room to fit the second bar.

Temper also has to do with how slowly or quickly something cools. You may be able to keep most of the temper by keeping the bar hot with a torch after welding and letting it cool slowly.

But I also wouldn't worry about it for a challenge car. IF it fails,make it better next time.

If FFR stuff works,does that mean mustang fox pieces would fit?

It's a Challenge car. It has to last a weekend. If it breaks, I'm sure there's a welder to booger it back together. Weld that mother.

Both of our Integra Chumpcars got a straight piece of 5/8 cold rolled with levers welded on each end for new rear bars. 24 hours later, neither is broken, and the links still slip into the holes without stress.

Works for me.

Hint:

VW Super Beetle, Porsche 924/944/968 all use the same length torsion bars in the rear suspension. They are 26-9/16" long and there's two of them in the rear end.

One could grab the torsion bar carrier/rear suspension from an early 924/944 or a Super Beetle and cut the steel splined sections off and weld those to a set of arms. Instant adjustable sway bar and you can replace the center piece for cheap as most people ditch the lightweight stock torsion bars for heavier ones.

Just an idea.

Guys, the bar twists along the long straight section. A couple have said it before, but just welding onto the ARMS is not going to compromise the thing in any meaningful way unless you go totally nuts with it and put hundreds of degrees of heat into the straight part of the bar ~6" away. Picture a splined bar with funky shaped fancy aluminum arms. They're plenty strong enough because they are not being twisted, only the center tube section is.

Not sure if this helps the topic, but I have heard of people narrowing bars by cutting out a center section (with mating angle cuts for the most weld area) welding and then sleeving the joint with tube of the correct I.D. and weld again. Yes the heat will affect the spring steel but the torsion in the bar at it's minimum in the center.

Don't know if thst would open up your junkyard bar options or not.

I'm hoping I can find a bar that is close to the Miata bar in general shape and weld tabs on the ends, well away from the straight section. IF I can find a suitable bar it would be easier to mount to the stock Miata mounts. If I can't find anything I'll add an NA bar to the NB one with clamps of some nature.
Does anyone know of another front bar with a straight section? Lots of GM stuff in the yards , but they usually have a pretty convoluted center section.

Second gen f body has a pretty straight center. Same with 2wd 90s full size gm trucks and s series.

I've got a S-10 bar you can have to play with.

In reply to Gearheadotaku:

Jeff, what's the diameter of the bar and how long is the center section from bend to bend?

From Googling pictures it seems a Jeep Wrangler bar is the right basic shape, without knowing any dimensions.

Madhatr wrote: Not sure if this helps the topic, but I have heard of people narrowing bars by cutting out a center section (with mating angle cuts for the most weld area) welding and then sleeving the joint with tube of the correct I.D. and weld again. Yes the heat will affect the spring steel but the torsion in the bar at it's minimum in the center. Don't know if thst would open up your junkyard bar options or not.

It's been a very long time since I had to do the math on this, but I'm fairly certain that the torsional stress on the bar is equal from end to end, unless there is some drag on the bar from friction with the mounts, which there probably is. But, the torsional stress doesn't decay toward the middle, then come back at the other end.

snailmont5oh wrote:

Madhatr wrote: Not sure if this helps the topic, but I have heard of people narrowing bars by cutting out a center section (with mating angle cuts for the most weld area) welding and then sleeving the joint with tube of the correct I.D. and weld again. Yes the heat will affect the spring steel but the torsion in the bar at it's minimum in the center. Don't know if thst would open up your junkyard bar options or not.

It's been a *very* long time since I had to do the math on this, but I'm fairly certain that the torsional stress on the bar is equal from end to end, unless there is some drag on the bar from friction with the mounts, which there probably is. But, the torsional stress doesn't decay toward the middle, then come back at the other end.

Actually thinking about this, yes I probably berkeleyed up that line of thinking.... maybe the welded section simply carries the force thru to the rest of the un altered spring steel?

In reply to Madhatr:

It would probably do exactly that, being stiffer. Which would serve to stiffen the bar (and possibly lead to cracking at the ends of the sleeved section).

DeadSkunk wrote: In reply to Gearheadotaku: Jeff, what's the diameter of the bar and how long is the center section from bend to bend?

The bar is 1" diameter and 29 1/2" from bend to bend. It flares out to 39.5 at the end links. If you want a thicker one, a 2wd S-Blazer is 1.25" in front.