Hi Purchased a universal sway bar from Speedway Motors to use on my 34, my problem is it looks too heavy and stiff.Has anyone out there used one of these on a similar car? Any feed back would be much appreiciated as I am reluctant to install it at this stag.
I have one on my '29 highboy sedan. Helps reduce body lean and I like it. Mine is a TCI on a TCI frame.
I've a '35 Chevy with a OT JAG IRS. I used a local OEM passenger car front sway bar on the IRS and yep, it handles a lot better than without. It was from a 6cyl sedan and not too heavy that it compromised ride quality, not that I'd throw it around like a sports car.
I read a couple of places that the rear sway bar should be about half of the diameter of the front sway bar. I think one of the threads was on Roddingroundtable.
My experience with my '41 Ford(with parallel leafs) was that it controlled body roll nicely but the trade -off was a rough ride, especially during a one wheel bump. The stiff bar tended to pick one side of the car. I disconnected it and the ride improved immensely
The problem [ or recipe for disaster ] is the word "UNIVERSAL", but it doesnt mean that it is no good. Firstly a Rear Anti Roll Bar [ RARB ] is basically a torsion bar that doesn't support weight of the vehicle. As with torsions they get softer as the get longer, also the longer the arms the softer it is [ the sides of a RARB ] If you mount the uprights inboard further it alters the motion ratio so it also gets softer [ people with "tubbed" leaf spring cars know this when they move the rear springs inboard the suspension has the same jounce stiffness, but the roll stiffness is terrible ] If you compare MacPherson Struts [ English fords] where the Anti Roll Bar is also a locating link mounted close to the ball joint the bar is quite small, but when the bar has links that are mounted inboard on the lower A -arms the bar is large [ 3rd gen Camaro ] The leverage ratio has to be multiplied 2 fold, so if you double the leverage the bar needs to be 4 x stiffer to have the same rate of stiffness at the wheel. Example . if you had an anti roll bar that was x amount of stiffness mounted at the outer balljoint [ 1:1 motion ratio ]. Then you moved it inboard 1/3 so it is now 0.66 motion ratio x divided by 0.66 then divided by 0.66 again = 2.29 so the bar needs to be 2.29 times more stiffness to get the same rat at the wheel. Now if you then lengthen the arms so the 1-1/2 x longer as well 1.5 x 1.5 = 2.25 so combining the 2 you would need a bar 5.16 x the original stiffness just by altering the leverage of the mounts and arms [ 2.25 x 2.29 = 5.16 ] The motion ratio of a beam axle is measured from the centre to the wheel vs center to the spring / bar mount.
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