Poly will squeak unless it is graphite impreganted, then they won't.
Poly is firmer, and will make the car handle better, but also ride stiffer. You will feel more of the road. For racing and performance they are the way to go, hands down. They will also last longer
BUT rubber is quiet, rides better and has better isolation from the road, not that our C3's are known for that anyway. So for highway or just crusing, rubber is better. They won't last as long, but I replaced the originals in my car at 30 years. Granted they were shot.
I used rubber in my front end, and will in the rear. Yes it is a disadvantage in autocross, but most of the time I use my car as a cruiser. A very spirted cruiser granted. ( ask the group going through Ohio to the gathering)
It all depends on what you are going to do with the car, and your goals.
Going to a fiberglass spring for comfort? Use rubber.
Going to a fiberglass spring (stiffer) for performance handling? Use Poly.
Original spring? Either way.
kstyer2011-05-28 07:22:54