I think the consensus on this board will be that the bushings are shot and need to be replaced. I've never seen a pair that weren't. When you put the new bars in you are adding a lot more stress on the suspension and it's going to move because the old rubber bushings can't handle the load. Your alignment settings will change as you are driving which will make the handling a little scary. Since you aren't taking the whole rear end apart, you can try it and see how it is but if you end up having to drop the whole rear end, definitely change those bushings at the least.

Do a search on here to see what a pain it is to get those old bushings off the spring plate. Everybody has their favorite method, I used a torch, 2 old screwdrivers, a knife and hacksaw and a wire wheel! It's dirty, time consuming work!

Seems to me a 2" hole will work fine, the bars are about a 1 1/2" diameter at the ends.

Good luck, and remember however you do it, take lots of measurements first. Read the how to article on this sight a few times through first.

I have used the torch method and do not consider it to be a "big deal". Perhaps I have been lucky on the spring plate bushings but have changed out two sets now and find it to be no big deal. The bigger issue is to make sure the delrin bushings fit properly. The last ones were very tight on the left side. To corner balance the car, I had to make sure and bounce the suspension good to get it settled but then I just drove the car and it seems fine.

I would absolutely change the spring plate bushings when you change the torsion bars. The old rubber ones must go to have the precision you want in a race car.

Big Dog

Thanks Ron. Maybe in early-mid November? I'll order the Weltmeister spring plate bushings from Paragon. What about the torsion tube mounts? Do those need to be replaced as well?
I have 29mm bars. Will those be ok with my 400lb front springs?

No go with the 30's.

Since you already have 29's it might be cost effective to stay with them. I know some guys run 28's but it seems most run 30mm. My car is finally handling good and I have 400lbs springs with 30mm bars. My car has lost a lot of weight and I've got the alignment pretty good(although I think the toe is out slightly again) and it has come alive on the R888's. If I could though, I'd go even stiffer but we're limited to the 30mm bars.

As far as the bushings go, I'm really not the person to ask. The spring plate bushings will be wasted and doing those are the toughest. The other ones however can be done at a later date but if you can afford it, it makes more sense to do them all at once. I still have the stock ones where the rear end mounts to the chassis because I couldn't get them out easily. I don't know how much I'm giving away but I really haven't worried about it until I found more speed in the driver. I'm running a little faster now but don't notice any movement in the rear end, all I feel is that the shocks can't always keep up with the torsion bars but the car is easy to drive at the limit and gets sideways without much drama.

My advice is to do what you can afford and get on track as quick as possible. Unless you are a prodigy, you will have a steep learning curve ahead of you and you'll find it's not the car slowing you down, it's the ballast between your ears!

I'll gladly help you with the suspension or anything else you need and if we use Steve and Ken's lift the job will be simple.

I'm in to help too. With air chisel and wire wheels the spring bushings come off fairly easily. If all else fails I have a cutting torch at home that will make easy work of the rubber.