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View Full Version : Is a sway bar needed?



Jeremy
05-19-2008, 12:10 PM
I have been playing with my VBP system for a year now, I think, and was wondering if a sway bar is needed. The reason I ask as it still had some funny quicks, even with the DA shocks. I started with switching from poly to rubber endlinks and ride got better with no noticeable change in handling. I then backed the rubber links off until I could just barely turn the spacer and once again better ride and this time better handling as the front and rear seemed more balanced and quicker turn in.

I then read a post about should endlinks be verticle and checked mine and they tilt back and in towards the center of the body. I figured the only I had to loose was some time, so I backed them off to where I could just barely get a double nut on the top and went for a drive.

No more popping and much much better ride. Turn in was sharp and body roll didn't seem noticeable. I even pushed it a bit in a round a bout and attained speeds higher than before, although body roll was more pronounced then before. The car felt more balanced front to rear and understeered at the limit. It had a very factory feel to it.

My initial conclusions are that the sway bar is binding and contributing to the pogo feeling when both tires encounter a large bump. I will drive some more with the bar as loose as it is and see if something changes, but if the car is tuned the way I want it, do I need a bar?

From my research of a transverse system on the vettes, I believe the initial goal was to do away with a front sway bar due to the better roll resistance of the transverse leaf so I know in theory it could work this way.

If not, at least I know I need to re work the angle of the endlinks as the bind seems detrimental.

Let me know what you think.

Jeremy
06-23-2008, 02:17 PM
I have pulled the endlinks and there is a drastic improvement in ride quality with no change in handling. Over rough roads, it is amazing how much more freely each wheel seems to move over imperfections.

I have some shock tuning left to do, but without a sway bar, the majority of the "bounce/vault/pogo" effect is gone.

6'9"Witha69
06-23-2008, 02:42 PM
You need shorter end links. I put a shorter pair from Energy suspension on and there was a noticeable difference in bind. I actually drove the car hard enough with the too tall end links that I bent the grade 8 bolts.

Don't know much about the traverse leaf setup other than what I have read from your threads, but to me if the part is not installed and setup properly there is no clear way to determine the benefit or detriment of it's use.

David Pozzi
06-23-2008, 09:37 PM
What you are doing is reducing front roll stiffness which makes the rear act stiffer.
Do you have a rear anti roll bar?
You need to correct the front bar end link issues. With weight on the wheels, the end links need to be pretty close to straight up, and the ends of the bar where the eye is should be close to level. Over tightening poly or plastic end links can bind the bar. The old rule of thumb for rubber bushings was to tighten until the rubber swelled to the diameter of the washers, Poly bushings would be way too tight if you did that.
David

Rick Dorion
06-24-2008, 02:26 AM
With a lowered car, the end link might only be about 1" or so to have it as you describe, David. Is this acceptable?

Jeremy
06-24-2008, 05:30 AM
I've got a factory rear ws6 bar and 150 or 200 pound rear fiberglass mono leafs (bought them used so I am not sure of the rate) with Edelbrock IAS shocks.

I agree the endlinks weren't the right height, but the bar is coming off completely the next time I am under the car.

The car is very balanced right now and rides very well so I can't see a need for the bar.

maldo
10-16-2008, 08:58 AM
I've got a factory rear ws6 bar and 150 or 200 pound rear fiberglass mono leafs (bought them used so I am not sure of the rate) with Edelbrock IAS shocks.

I agree the endlinks weren't the right height, but the bar is coming off completely the next time I am under the car.

The car is very balanced right now and rides very well so I can't see a need for the bar.


Going back to the sway bar theory (so you have concluded no front sway bar is needed? ) what about the rear sway bar I keep hearing that it is not need in the rear also …

Jeremy
10-16-2008, 10:47 AM
For me, with the VBP setup up front, I have found that I don't need a sway bar. Since I originally posted I have continued to drive without one and don't see me going back.

I am still running the rear bar to keep things balanced. I think the best conclusion I can give, is every car is different and needs to be tuned. Sway bars are tuning aids.