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View Full Version : Stupid question: Poly bushings on the front



derekf
12-05-2004, 06:20 PM
Ok, yeah, it's a stupid question and I should know better:

It's known that poly on the rear control arms (on A-bodies) is not a good plan because the rear end needs to twist and with poly it binds up.

What about on the fronts - I can't think of any reason why poly (or other low-deflection material) wouldn't be just fine on the fronts as the bushings shouldn't need the ability to twist. Is there indeed any reason (other than NVH) not to run something stiff on the front?

David Pozzi
12-05-2004, 07:15 PM
I rode with a buddy in his 69 Z/28, he drove me around Laguna Seca on an open track day. As he drove through the pits, I could tell the car had super stiff front suspension and asked him what rate ft springs he had. He told me the front coils were STOCK.

I think this is a worst case deal because he'd installed them long long ago and never done anything to them. When he jacked up his car to change back to street tires, the car went SQUEEK SQUEEK SQUEEK. Each time he pumped the jack handle.

The big thing is the stock rubber and polly bushings contribute an unknown amount of spring rate to the front end. If the polly slips on the steel sleeves like is is supposed to, there is little effect, but if it sticks, and it's a sticky material, it can have quite an effect.
Delrin bushings are the best in my opinion, I'd use rubber as a second choice, polly last.