SAS swaybars and front bar question

[Nate]

I have a set of SAS swaybars with all of the hardware and bushings but don't have know how they bolt up. Actually, I know how the back mounts up by these pictures





The front one is a mystery. Supposedly it mounts underneath the steering rack rather than behind it and I have to drill holes in the frame rails to mount it. Here is a picture of them



The internet rumor has been that the front bar deters from the handling of the car since the double wishbone suspension is tied together with a swaybar. However, in a recent thread you guys suggested installing both front and rear swaybars with the understanding that a little traction will be lost. Should I install it?

Car setup is this:

'85t no swaybars, Kilen springs with bilstein HD's

Alignment

+2.5 degrees caster, -1.5 degrees camber, and just a "touch" of toe-in.

I don't do autox or track it, just like to throw it hard into curvy roads.

[squaab99t]

I have a set of SAS swaybars with all of the hardware and bushings but don't have know how they bolt up. Actually, I know how the back mounts up by these pictures





The front one is a mystery. Supposedly it mounts underneath the steering rack rather than behind it and I have to drill holes in the frame rails to mount it. Here is a picture of them



The internet rumor has been that the front bar deters from the handling of the car since the double wishbone suspension is tied together with a swaybar. However, in a recent thread you guys suggested installing both front and rear swaybars with the understanding that a little traction will be lost. Should I install it?

Car setup is this:

'85t no swaybars, Kilen springs with bilstein HD's

Alignment

+2.5 degrees caster, -1.5 degrees camber, and just a "touch" of toe-in.

I don't do autox or track it, just like to throw it hard into curvy roads.

I really hated the understeer so, I removed my stock front and left the rear. ('89 900)
I'm also running shorter but higher spring rate springs.

That front bar looks a bit funny with the added curve in the center. Are you sure it is for the front 900c? The ends of the rear also look different than what you have as your example.

[99Super]

I had a sway bar on my 99 for 1 season but it generated way too much push and unloaded the inner tire too much for either Auto-X or hillclimbs, so I'm against them in general.
I also took it off my 86 SPGs.
I add the rear to every 99/900 I get asap...

john

[Hans]

I prefer a front bar on a daily driver, but remove it from cars I drive for fun.

[Luke]

I think the whole swaybar debate comes down to driver preference somewhat. If you feel comfortable with how the car is behaving, regardless or whether that is or is not the setup that provides the ultimate grip, YOU will be faster.

I've tried all different combinations of stuff and I find that I don't like sway bar's on rough gravel. The chassis is most willing to get tossed into woops and waterbars and washboards like this and come out alive.

On twisty but smooth tarmac roads I run with sway bars front and rear. I find that the reduced movement of the weight around the roll center translates to a chassis that has a quicker response and its more nimble on its feet and is more predictable.

[DrewP]

Bars (and bar stiffness) is also highly dependent on the stiffness of the ride springs - depending on who you talk to and what form of racing (or street-ing) you do, the ARB's will be different.

Considering the whole system you would size an ARB to be some percentage of total roll stiffness - the percentage changes with driver, racing surface, suspension geometry / type, and car weight and CG height.


Sounds like a lot of babble, I'd like to make an adjustable ARB (or maybe even both) for my car, but that's a ways off, so we'll see when we get to that bridge.

If by some miracle it handles proper when it's all polished up I may lose interest, so we'll see.

[Nate]

I think the whole swaybar debate comes down to driver preference somewhat. If you feel comfortable with how the car is behaving, regardless or whether that is or is not the setup that provides the ultimate grip, YOU will be faster.

This sounds dumb but the '87t I used to have felt better in the twisty roads with front and rear swaybars and stock springs than my '85 does with stiffer springs and shocks. I think I'll put both in.

[SwedeSport]

It is easy to change the setup if you don't like it. In a few hours you can be ready for a whole new track or road condition. I have changed it 3-4 times this year. Set yours up how you think it should be. And adjust as you go. Try to drive other peoples cars when you have an opportunity and you'll be a better judge of your own setup. Its all kind of trial and error. The forum can only share some of the trials. What works for you can only be found by experimenting.

[Turbotaf]

It looks like you have the Addco sway bars.

Rear instructions:
http://static.summitracing.com/global/i ... co-405.pdf


Front instructions:
http://static.summitracing.com/global/i ... co-193.pdf

[Nate]

It looks like you have the Addco sway bars.

Rear instructions:
http://static.summitracing.com/global/i ... co-405.pdf


Front instructions:
http://static.summitracing.com/global/i ... co-193.pdf

Thanks for the links. Honestly, I don't know what I have. I have obtained a set of instructions from SAS. The front one seems to match theirs as far as hardware and installation. The rear one (405) though is different. The rear seems to match the Addco one judging by the hardware I have for it but the instructions you posted are so vague they aren't helpful.

[Nate]

With further investigation I'm confident that I have a set of Addco bars. The front mounting system seems okay. There are L brackets that bolt onto the inner lower ball joint bolt and the support brackets bolt to the frame rails underneath. Seems pretty sturdy. However, the rear is a different story.

The rear bolts up just like the one pictured, with muffler clamp holding it onto the axle. For the ends of the bar, they want to to drill holes in the floor pan and run a square U-bolt through the floor and bolt up to the bar. Seems pretty hokey to me...makes me want to through them in the garbage can.

[Jordan]

What would be the difference in stiffness between doubling up a stock bar, vs. the addco rear bar? More weight for sure, but it may get you the desired result without too much mounting trouble.

[Nate]

I had a crazy thought this morning after working all night.

What if I took a stock sway bar and replaced the center section with like a 3/4" 1040 steel or so rather than doubled them up. Of course it would probably easier to just double them up.

I used to work at a place that made "wire" formed products. When I worked there, we couldn't bend 3/4" steel but maybe things have changed.

[DrewP]

If you're thinking of going that route you may want to consider making it from tube, the computation to find torsional stiffness is fairly straightforward, you need to decide what your desired cross section (in the form of area moment) will be, then find a size tube that gives you the right area moment that can be purchased, it will be a fair bit lighter, and easier to form a 'U' shaped one from one piece.

There's an easy check for torsional bucking too (don't want the wall to be too thin).