LCA Bushings and Other Bushings

RedFish said

The factory rubber was used as isolators. A lot of hard parts like bronze bushings and/or heim joints would transmit through the steering linkage and chassis. Steering wheel vibrates along with seat and everything else.
Shock absorbers do only that, absorb shock. They cannot isolate the steering linkage.
To replace all the worn out parts with OEM type can make a 30 year old car drive just as it did when new.
A lot of performance minded aftermarket parts turn it into something different. The choise is yours.

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That's right. Nylon has about zero damping. Poly has some damping and rubber has the most damping (and rubber durameters and thickness can and are selected by the OEMs pretty carefully, aftermarket who knows!).
The reason for using nylon is that with very sticky tires (ie r compound) in competition on good pavement, it helps with camber.

For those looking for more performance in this area, the place I recommend most people to start is with the sway bar bushings. Switching them effects the transmission of vibration very little, but makes the bar more effective and with less delay. Even so, if the end link bushings are changed to poly without using much thicker steel washers then often the washers will get punched through by the steel sleeve. Also sometimes the poly bushings will compress and not bounce back, so the end links need to be checked for tightness now and then.

I will say that some shocks have a poor high frequency control that will transmit to the entire vehicle. Usually, with single and most double adjustable shocks, the adjustments mostly effect the low frequency response. Hopefully this year I'll get to experiment a bit with the shock settings on the course as well as off. Right now it seems like a little less damping may be better.