Last winter I did some upgrades to the stock suspension on my '69 Z-11 which has about 97k miles on it. The rear multi-leaf springs were replaced with approximately stock weight/height new ones but also added poly bushings on the front and rear spring mounts/shackles. The front sway bar was also replaced with a 1 1/8" with poly bushings (frame & A-Frame). Also replaced the shocks with a nice set (front & rear) of gas charged.

I also replaced the bias belted tires with a nice set of p-215/70-15 BFGoodrich Radial T/A's.

So far the replacements have made a wonderful change in the handling and ride on the car. Next thing is to get the front end re-aligned using Herb Adams recommendations for street (3.5 degrees + caster, 1 degree + camber, & 1/16" toe-in).

One of the things I have been considering is replacing the 6 sub-frame body mounts and when I do, getting a set of poly's for this. At first glance, this seems that it might help the body sit on the sub-frame more solidly. This said, that also might detract from the ride. I am looking for a smooth riding solid stance, but not one that rides like a truck.

Any one have any experience with poly sub-frame mounts or comments?

Bruce

I put energy suspension poly mounts on my 68 vert this winter... suspension setup is similar to yours, except i did g/s mod and thirdgen steering.

Don't see any down side at all to the poly body mounts. Car is much more solid and stable than it was with worn out rubber.