Pro and Cons of a 1.25" Rear Swaybar

[Stg1Regal]

Been snooping around looking at front and rear sway bars...

Found a BIG rear one... 1.25" ... Could this be used in the Pro-touring arena or just drag racing?

If so what would be matched for a front swaybar.

Currently I have Grand National front and rear swaybars on my 82 Regal with poly busings in the arms front and rear.

Plan on stepping up the suspension to the better tubular designed trailing arms that do articulate on the rear, and up front, for the taller balljoints , correct uppers.

Just curious if I could use that rear swaybar.

ALso I will be stepping up to 17" tires and rims, wide as I can stuffed in all 4 corners.

thanks

[ccracin]

Chris,

Unfortunately, that is a tough question to answer. Swaybars are just a piece of the chassis tuning puzzle. The size needed is based on the rest of your suspension and handling characteristics. There are many schools of thought and if you ask 10 people this question most likely you will get 20 answers or more. Here is my hit list when looking at this. I want the softest springs possible in the vehicle that will hold the vehicle at ride height. After that it is about roll angle. How much do you want the body to roll? You want the front and rear to be balanced. That means you want the front roll angle to be as close to the same as the rear roll angle as possible. This is where the sway bars come in. You can then limit the body roll with the bars while keeping the springs compliant. This will allow the vehicle to handle humps and bumps better than a stiffer sprung vehicle. It's then about compromise. If you cannot maintain the roll angle you want with a reasonable sized bar, you then have to increase your spring rates and start the testing process over. After you get the major characteristics close to where you want them, then you can fine tune with the shock package.

I know this didn't answer your question, and it was not supposed to. I just wanted to convey that the suspension is a system and should be treated as such. Just throwing a bigger sway bar on may do quite a bit more damage to to your handling than you think.

I would suggest picking up the book "Chassis Engineering" by Herb Adams. Read it 10 times or until you get the concepts he discusses. It won't make you a chassis expert, but will help you make better decisions on your part choices.

Good luck!

[Buick Grand National Guy]

You probably have a drag bar but it really depends on the length of the arm! Closer arm it to the bar, the stiffer the setup will be. Shoot me your e-mail and I will send you a PDF file with info on available chassis-mounted rear sway bars. File includes torsion capacity (lb/in) of many of the sway bars.
Conrad

[hp2]

Thats big. Is it tubular or solid? If tubular, whats its wall thickness? Where does it connect, as this impacts its applied rate.

To decide if it would work, you would need to know front/rear weigth bias of your car to determine the amount of roll couple required for balance. Roll couple is determined by front spring and sway bar rates and rear spring and sway bar rates determined as a percentage of the roll couple. BTW, the roll couple is not a direct percentage of weight bias either. So there is a bunch of math required to figure it all out, after you figure out weight distribution.

[Buick Grand National Guy]

I have attached a .PDF file containing most of the chassis-mount rear swaybars for G-Bodys.
Conrad

[Zspoiler]

What size front bar do you have? Do you want the car to handle ? Because road racing and drag racing are two diffrent animals.Everything needs to match up. I have both a 1979 Z-28 Camaro ,and a 1981 El Camino SS. Both are pro touring cars so they are similar.Both have big Bars on them. But if I wanted to drag race I would have to put on a small front or no sway bar.With no rear bar.Because you want the nose to rise and the rear end to squat to get the most traction to the rear wheels

[Chassisworks]

Chris,
If it's the Chassisworks 1.25" rear ARB it's really designed for drag racing only. It's a solid bar with a 6.70" lever length. It's designed for keeping cars flat when launching on slicks with up to about 2000 hp. Not to say you couldn't turn the center down to get the rate you need.