The bushings in the front suspension of your muscle car have two main purposes. One is allowing the pivot points to move and the other is to isolate and dampen vibrations transferred from the road. GM uses rubber because it does a great job at dampening and yes it allows the pivots to move.
There are two main problems with rubber bushings. First, they are relatively soft and will fall apart over time. Second, when you turn a corner the bushing is subjected to an increased load and if the bushing deflects, then a lot of things can change like caster, camber and toe settings. Over time this increased load can also permanently compress rubber affecting the alignment. Since most of the cars we talk about here in Super Chevy are 30-plus years old, the factory rubber bushings are probably on their way out anyway.
So what is the cure for the rubber bushing woes? An upgrade in the way of polygraphite bushings from Performance Suspension Technologies is a definite solution. Unless you have been trapped in your garage for way too long, then you already know the benefits of polygraphite, but just in case we will go over it. PST explains it this way: "Polygraphite is a graphite-impregnated polyurethane high performance bushing designed for street, strip or track driven cars. The bushings feature a higher durometer (firmness) that will last longer and provide a solid base for your suspension. Now your ride can have the road handling characteristics of polyurethane bushings with virtually no deflection and the lubricating qualities of graphite."
There is a big urban legend running around that all polyurethane bushings squeak, but this is not entirely true. Any bushing will squeak if you install it wrong or don't lube it enough. Your best weapon against the squeak beside a proper install is the supplied grease. It forms a tough, durable, chemical resistant film of lubricant to prevent metal-to-metal contact even under severe shock loads. Only a small amount is required to properly lubricate bushings and metal components and to prevent corrosion.
When ordering a front end kit from PST, there are going to be a few thing you will need to know about your vehicle and a full list can be found on the company website, but here is what you need to know when purchasing a Chevelle kit. If you have a '64 you need to know the diameter of center link (13/16- or 7/8-inch). On the '66 like the one covered in this story, you'll need to know the diameter of lower rear control arm bushing (1.67- or 1.90-inch). In our case the car had 1.90 bushings. For the '70-72 vintage, look at the lower rear control arm bushing and see of they are round or oval.
If you add more components to your order like a center link or a set of shocks PST will give you a little discount. All the stuff you see in this story set us back $621.00 and was installed over a weekend. There are two tools that made this job a little less time consuming, an air hammer and a ball joint press. The air hammer isn't really a must as you can still use a traditional hammer and a punch or chisel. The ball joint press can be rented from some automotive stores like AutoZone or can be purchased from tool suppliers like Harbor Freight (PN 4065-1VGA, $49.99). The tool uses a big C-frame, special spacers and collars to drive the bushings and ball joints in.