In the late '80s Doug Rippie...
In the late '80s Doug Rippie discovered that what was ideal for the street wasn't necessarily the best thing for the race track. Getting the Corvette to squat during acceleration could actually be a good thing. The idea is that as you exit a corner you want more weight transfer to the rear. This gives you a little extra traction on exit. Now you can just reverse this process when you brake on corner entry. A little extra transfer to the nose plants the front tires just a little bit better. The factory bracket is on the right. The one on the left is from Doug Rippie.
Polyurethane bushings are not all the same. The hardness varies widely from on company to another. Some are really soft and deform under use. Keep in mind that polyurethane is not like rubber. Once it deforms it will stay deformed. I used some soft polyurethane bushings in my rear control links and they actually ovalized in the course of a year. The stiffest polyurethane bushings seem to come from Vette Brakes and Products. I've never had a problem with their bushings. At this point they're the only ones I use. Now it's just a matter of getting all the other ones out of the car.
If you have over 100,000 miles on your C4 you're probably a candidate for polyurethane bushings. They're not as easy to install as some would have you believe but it's not all that bad. You can do them on one of those weekends when nothing else is going on. It's just a matter of taking your time. New bushings may very well be the least expensive way to revive your old tired suspension. I think it's worth the effort, just don't believe all the hype that you're suddenly going to pull 2.0 Gs in a corner.
| Difficulty Index - 3 Wrenches |
| Anyone’s Project: no tools required | 1 Wrench |
| Beginner: basic tools | 2 Wrenches |
| Experienced: special tools | 3 Wrenches |
| Accomplished: special tools and outside help | 4 Wrenches |
| Professionals Only: send this work out | 5 Wrenches |
When you use the Rippie bracket,...
When you use the Rippie bracket, you change the angle of the two trailing arms. This changes the anti-squat and anti-dive characteristic of the car. One of the things you should consider is replacing the bushings in the ends of these rods with polyurethane bushings that everyone sells. I really haven't seen a need for the adjustable aftermarket trailing arms with heim joints on all the ends. Those are just wretched excess.
This is a stock C4 toe control...
This is a stock C4 toe control rod system. Under the rubber boot is a ball socket, and wear can take place in the ball and socket. If you have excessive wear in that area, the toe setting will change as you drive down the road. This is from an early C4 and replacement parts are no longer available. You can replace this with one from the earlier cars or the heim joint arrangement from Vette Brakes.
This is the Vette Brakes system....
This is the Vette Brakes system. With this arrangement there is absolutely no play in the system. The only downside is that it might be a little noisier but I can't tell on my car. My only advice is that you must use the grease seals from Seals-It if you use this set-up on the street. The one thing I really love is how easy it is to change the toes settings with this unit. Just turning the control rod lengthens or shortens the rod. Once you have the toe setting where you want it you just tighten the jam nuts.
This is how you check for...
This is how you check for play in the rear suspension. If you can move the wheel around with your hands in this position you have wheel-bearing play.
This is the outer end of the...
This is the outer end of the Vette Brakes toe control rod system. In this instance, I don't have the Seals-It rod end seals installed.
I haven't felt the need to...
I haven't felt the need to heim joints at this point. Heim joints would be nice but at this point I'm just not sure the incremental improvement would be worth the cost. The bushings here are polyurethane but Delrin would be even better. That is if anyone made Delrin bushings for Corvettes. Corvette suppliers all seem to love the polyurethane bushings for most applications. I think it's a cost issue. Also Delrin can be a little more difficult to fit properly. They need to be machined to fit the specific application.
This little rubber seal makes...
This little rubber seal makes heim joints streetable. Ok, almost streetable. Until these were created heim joints were strictly for the race track. At the end of the weekend every rod end was checked and cleaned. Normal road dirt destroys heim joints.
There are a few things going...
There are a few things going on here. First, the red bushing for the spring is polyurethane. That's no big deal and it's really easy to do. I'm not sure you get anything from the use of polyurethane in this application but it's cheap and easy to do. The long bolt you see is a lot more important. The bolt is much longer than the stock bolt and it allows you to lower the rear of the Corvette. The third thing is the camber control rod from Vette Brakes. The real beauty of this system is that you can easily change the rear camber. The left decal you see on the rod means that it's a left hand thread.