How much better are poly bushing vs rubber on sway bar?

[Redsquall]

Hey guys,
my car is at the DMC shop and waiting on a shipment of poly bushings which will probably delay the completion of repairs 2 or maybe 3 weeks. Worth it or just go with rubber? Thanks

[powerline84]

many people swear by Polly on the sway bar. I myself have and am going to be running Toby from Northwests polly sway bar bushings. I say wait

[Redsquall]

many people swear by Polly on the sway bar. I myself have and am going to be running Toby from Northwests polly sway bar bushings. I say wait

Interesting. How do people describe the difference in feel or other benefits? Thanks

[Mike Griese]

"Better" is a relative term. The important metric for a bushing is the durometer - how hard is it when you try to change its shape. Just saying poly bushing isn't enough. There are hard polymers, there are softer ones. How do they compare to the original rubber bushing in terms of durometer?

Most times, poly bushings are harder. This means they will not compress as much as a rubber bushing given the same load. In a suspension, this means a couple of things. First, a lot more road noise and vibration will be transmitted to the cabin and steering wheel. Rubber bushings tend to dampen that harshness out, poly bushings don't. Second, the steering will be somewhat more responsive, as there is less compliance in the suspension. This may or may not be good, as a more responsive car reacts to changes quicker - it will turn in quicker, which means load transfer from front to rear and side to side will be quicker. This is important to understand with a rear engine layout like the DeLorean - there will be a greater tendency to oversteer.

Just doing the ARB won't change things too much compared to replacing your old bushings with new rubber ones. A lot of times people confuse the change by comparing new poly bushings to old rubber ones. The real comparison is new to new. That sais, going to a fresh set of tires will probably improve handling more than just going with poly bushings on the ARB.

[DMCMW Dave]

My personal preference is poly bushings on the sway bar clamp and ends ONLY, not on the control arms (need to have some "give" there). My recommendation is the kit from Toby at DeLorean Northwest.

[Bitsyncmaster]

One good thing with poly over the OEM rubber on the control arms is there is no need to "center" the bushing. That requires torquing the bolts with correct weight on the wheels.

[David T]

Dave S is correct, some bushings have to move in more than one plane, in those applications you really do need the compliancy of rubber to allow for that. In places where the movement is purely in 1 plane, Poly can be a good choice. When installing poly bushings you should use silicone grease. I have seen where the poly kind of bonds itself to the parts and doesn't allow easy movement. The brackets where the ARB attaches to the frame can be poly. Where the ARB attaches to the LCA should be rubber to allow for easy movement in an arc. By stiffening up the suspension with poly bushings you can expect more vibration and "road feel" transmitted into the frame and steering gear. Some people, not expecting that, are disappointed with poly.

[opethmike]

As someone who has owned numerous sports cars and has spent A LOT of time modifying them, I can tell you that unless you drive your car real hard (harder than you should be on the street), or take it autocrossing or to a circuit, poly bushings are not worth it.

Under normal driving conditions you will find zero benefit from them, but you will sure as heck still experience the negatives. Harshness, etc, as described by the guru in the previous post.

[David T]

If you have ever watched the front wheel of the Delorean move under heavy braking you will appreciate the poly bushing. That ARB, aka sway bar, does "double duty". It also maintains the front wheels in the correct fore-and-aft position and transmits the braking forces into the frame. The rubber allows the wheels to move a considerable amount. The poly will hold the wheels much better.

[opethmike]

Nope, never seen that. I don't even own a DeLorean.

[Redsquall]

Thanks very much guys. Really appreciate the views and insights

[DMCMW Dave]

Under normal driving conditions you will find zero benefit from them, but you will sure as heck still experience the negatives. Harshness, etc, as described by the guru in the previous post.

They can also be squeaky. Having to periodically take your suspension apart and grease it is no fun.