Thread: air bag suspension. problem

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my friend has an air bag setup on the front only of his 48 buick super and when its lowered at all from the highest height it gets a severe toe out. did the installers do something wrong or is this supposed to happen?

Generally you will get severe camber changes, but not toe in or toe out. Evidently the tie rod length is changing in relationship to the steering arms and pushing the arms out as the car gets lower. Does the car have rack and pinion steering? Reason I ask is I envision the rack being mounted to the frame and as the car drops the arms are forced out and pulled in as it gets higher.

Pictures would help a lot.

Don

My '35 chevy is the same way. Unfortunately most suspension designs don't have the a-arms and the tie rods traveling on the same arc. Most suspensions develop negative camber as they reach thier limit of travel. Especially cars designed with limited travel. Trucks designed with a lot of travel aren't so bad. Toe out is a result of negative camber. As the wheels pull in a the top, the arc that the tie rods travel don't allow them to pull in at the same rate as the upper a-frame so the tires get pushed out at the front by the tie rods causing toe out. They even named a car club after it "Negative Camber".

We see this alot with the gm front suspension packages. Ours dont do that much at all. We use a heavily modified mustang II front suspension design. We have taken a lot of the problems with the toe out of our design with a new drag link.

Yea when you set it up that is why you do your alighnment at ride height, pretty much every other height changes something As long as it drives good at ride height your fine. I set my alighnment up pretty low on my dually, but it would got to a postive camber when it was raised up almost full.

That is true.. I agree with this totally on a stock use front end. I didnt like that you had wild movement when raised and lowered so we tried to design one that gets really good alignment through all the travel. I think we did it pretty well.

Modify the frame, raise the rack up or down so that the tie rods are level with the gorund at ride height. Then up or down you get the same effect. basically at ride height your tie rods should be level with the ground (longest point). From the sounds of it, the tie rods are pointed down (from frame to wheel) when the car is raised all the way up, thus lowering it you are lengthening the arms (straight line distance from rack to spindle mount) but your tie rods are a solid length.

not an air suspension problem... thats a geometry problem. Airsprings are not going to make that front end do anything that is does not do through normal suspension travel. The only difference is that you can physically see whats going on with an airsuspension because you can manipulate the height.... kind of hard hanging your head out the window watching your front tires at 80. You mentioned that this is on a 48 Buick ... is this the OE front crossmember he is working with ir is this an aftermarket crossmember? Has it been subframed ?