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Fri Mar 10, 2006 8:17 pm

Hi, all.

What's the word on narrowing a sway bar? I have a stock length 3/4 inch SAW front sway bar that I don't need. What I will need is a 3/4 inch sway bar for a 4" narrowed beam.
Is it feasible to cut the bar in the center, remove the 4 inches, sleeve the joint and then weld it back up? Will the joint affect function?

By the way, for what it's worth.....I suggest that anyone considering a narrowed beam should install the intended brakes and spindles on a stock beam BEFORE they order the narrowed beam. I'm now the proud owner of a 2" narrowed CB L/P beam and 2" narrowed sway bar that I don't need! Had I mocked this up first with the stock beam on the car, I would have known that what I need is a 4" narrowed beam! Now I'll have to lay out more dough, and then try to sell the 2" stuff. :evil:

Fri Mar 10, 2006 9:01 pm

I just narrowed my beam 4" too. I saw a swaybar from aircooled.net that might work for you. Unfortunately it runs between the trailing arms where the bump-stop normally is located. I can't use it since I welded my bump-stops back on.

I might try to fab my own using the splined bar and arms from this place.

http://www.hrpworld.com/index.cfm?form_cat_id=216,212,363&action=category

Sat Mar 11, 2006 11:55 am

I narrowed my beam over the winter by 3 inches. Any swaybar larger than stock is overkill for my application so I did just what you described. I don't have any miles on it though so I can't tell you how well it will hold up. I did talk to a guy that makes swaybars for mid 80's gm cars and said that that is a pretty common practice. I have a feeling a 3/4 inch bar on a 4 inch narrowed front end will be way to stiff but only one way to find out.

Mike
59 single, 66 bug, 69 bus, 73 super
Member of the Ddk

Sat Mar 11, 2006 1:30 pm

If you cut and narrow a factory sway bar the bar just became usless. I would suggest ifyou really want a say bar (not a bad idea) to just make an entire new one that would properly fit a 4" narrow. find some 3/4 bar tubing and fab it up

Sat Mar 11, 2006 4:28 pm

I think cutting , sleeving and welding in the middle would be pointless. A sway bar is a torsion spring , I think cutting in the middle will harden and weaken the bar at the welds.

I would suggest cutting the ends off at the 90* bend , shorten the straight center section then weld the ends back on. This may allow the center to act like a torsion spring. Then again it may not work . The bar could brake , so be carefull. Good luck.

Sat Mar 11, 2006 7:50 pm

I'm not a metalurgest - just a hacker with a MIG welder, but I'm pretty sure heating and welding the spring steel on the torsion bar will cause it to loose it's spring and I think it would probably just bend or break where heated - I wouldn't trust it. That's why I'm thinking the splined bar and clamp-on arms might work.

I know it's pretty common to re-arch leaf springs. Does anyone know if they heat and bend the springs? Maybe they could re-bend a torsion bar?

Sat Mar 11, 2006 8:49 pm

Thanks for all the thoughts on this topic.
I guess the way I see it is this...
If I cut and weld the bar, and do it well, the bar should retain all the structural integrity it had beore. I'm not worried about the bar breaking. A well done weld, by definition , leaves the material at least as strong as it started out.
I do agree, however, that the heating of the metal may have some adverse effect on the torsional properties of the metal. I'm hoping that the effects, if any, will be minor. The bar may be stiffer and less flexible in the center, but the twisting forces should still be transmitted through, right?
The decision is made. Since the bar is on hand, paid for and not needed, I'm going to attempt the modification. Worst case scenario? The bar breaks. Breakage is not a safety issue, and I can always buy a new bar if need be. Best case scenario? I make a working 4" narrowed bar and save some money. Wish me luck!

Sat Mar 11, 2006 11:45 pm

In a past Hot Rod magazine about suspension, a company called Wheel to
Wheel in Mi., did it on a custom setup. They made the seam in the middle,
but cut it at a 45 degree angle. The edges may have been beveled before
welding, I don't remember, in addition to a sleeve welded over the seam.
They stated it stiffens the bar 15%.
Hope this helps.

Sun Mar 12, 2006 7:56 am

Thanks, Lenny! Now I feel even better about my decision to modify the bar. If I remember, I'll try to take pictures and post them here.

Sun Mar 12, 2006 8:07 am

Yah - definately post after your done. I'm thinking I'm just being paranoid about cutting and welding the bar.

Sun Mar 12, 2006 9:38 am

Franklins fabs narrowed sway bars. Give him a call or try [email protected] or their website www.franklinsvwwerks.com
I have one on my car, works and looks great.

Sun Mar 12, 2006 4:36 pm

mailman wrote:
If I cut and weld the bar, and do it well, the bar should retain all the structural integrity it had beore. I'm not worried about the bar breaking. A well done weld, by definition , leaves the material at least as strong as it started out.
I do agree, however, that the heating of the metal may have some adverse effect on the torsional properties of the metal. I'm hoping that the effects, if any, will be minor.

Your understanding of metalurgy is completely wrong. When a sway bar (spring) is made, they first select the right alloy of steel. Only certain alloys can be made into a spring. The bar is cut and bent into the right shape. Next it is heated until it is glowing red hot. While that hot, it is quenched in oil to cool it at a very fast rate. This quenching makes it extremely brittle, but also hard. To give it the spring effect, they then heat it again until the steel starts to turn blue (not glowing) then they allow it to cool slowly. After these steps it will be able to be bent and will spring back to exactly the same shape it had before being bent (it is a spring)
When you weld on it, the first problem you create is that the alloy of the steel rod (or wire) is completely wrong for the alloy of the spring. Then in order to get a good weld, you have to get it hot enough that it will remove the tempering from when it was originally made.
Eventually the bar will break at the weld. Then you have a 2' long bar flopping around at speed. If you weld it at the point where it is bent, you will have twice the problems.
The best way you could shorten it is to cut it at a shallow angle so you get 4" of overlap, then make a sleeve and drill a bunch of holes through it. Then bolt the whole thing together. No welding, no altering of the heat treating.
Depending on the shape of your current 2" bar, you could just cut the ends off and push it in deeper. That worked for me.

Sun Mar 12, 2006 6:16 pm

Bruce, it certainly sounds as if you are much more familiar with metalurgy than I am. I am by no means an expert. I had just hoped to save a few dollars by re-using the bar I have.
Maybe, rather than ruin the stock length Sway-A-Way bar that I have, I should just sell it and buy the 4" narrower bar that I need. I was hoping to avoid the hassle, but.....

Sun Mar 12, 2006 6:59 pm

You will ruin the temper of the sway bar by heating it or welding to it. It will not be "spring" anymore, as stated above.

It is also very difficult to drill spring steel, depending on its exact temper.

What you can do, or what I plan to do, is grind a large "flat" on each end, and splice them together with a sleeve and some set screws.

Good luck. Just dont weld to it or you can just throw it away.

Sun Mar 12, 2006 7:12 pm

sbnova wrote:
It is also very difficult to drill spring steel, depending on its exact temper.

There is only one tempering process to create a spring. That tempering process restores some of the ductility and softness that was lost in the quenching process. Typical High Speed Steel (HSS) gets a similar quenching process, but without the tempering that follows during spring manufacture. This means HSS will always be much harder than any spring. Or in other words, it is not difficult to drill spring steel with HSS.

Mon Mar 13, 2006 8:24 am

I know that I can easily redrill the dimple in a set of vw front torsion leaves. I have tried to drill a hole in a set of leaf springs on a pontiac and went through numerous bits and barely made a mark on the spring.

Mon Mar 13, 2006 2:15 pm

You have to use coolant on the drill. A little too much heat will temper the tips of the drill making them soft. I'm sure you've all seen a drill tip get blue? That is the colour that will make it soft. Harder steels may require carbide. There is no metal known to man that can't be cut with carbide.