Rear Suspension Binds

[ask0329]

I'm following the advice of a vetern driver at my track but like to hear all sorts or options for research and learning purposes.

I have an underslung 3 link. The car is older a 99 or 2000 or so but still in really good shape. Are underslungs even built anymore? I'm thinking this was built prior to the rear suspensions getting that radical and moving allot.
On the Left rear part of the underslung was notched out to allow the rear end to drop. (this is how it was when I got the car). After a few races we noticed the rear end was rubbing/hitting/binding on the underslung where it was cut out.
On the Right rear we noticed that the rear end was hitting the top of the underslung chassis. The RR was not notched but still the box tubing. Also noticed that on the RR arm, the bolt that holds it to the cage was rubbing against the outside of the underslung section.

[powerslide]

Alot of older cars have these problems. I wouldnt worry about the LR too much if you have around 4in's of drop on the LR.
The RR hitting is a problem and without alot of work likely not going to be fixed.
i was a little confused where it is actually rubbing on the RR. Is it the overrail or under rail? whats hitting?
I spaced my trailing arm mount out on the rearend side. Also went from a 4off to a 2off wheel. You will have to make other changes to offset the wheel offset change. It's unlikely you will notice the trailing arm movement.
If moving the mount of the rearend isnt enough and you have more room to the right may need to install a new mount further out on the frame. If not only other option is to move it inside and makes it tough to adjust. If i have further confused you post some pics of whats hitting and maybe we can give you an option of how to update it.

[ask0329]

the right rear bar/trailingarm comes off the chassis back to the "birdcage" and the bolt head is on the inside of the cage with the nut on the outside of the cage. when the rear end drops so to say, the bolt head is scraping and wearing a groove on the outside of the underslung chassis.

Also when the rear end drops both tubes are hitting the underslung portion of the chassis under acceleration.

Its a home built car that I picked up used so who knows how or what the original builders built it. I'm giong to cut the underslung portion right out of it and run new bars up and over like the newer style chassis.

[LM14]

Nothing wrong with an underslung frame, just built a new one myself.

I would cut the lower square tubing out and replace it on both sides. Do one side at a time. Make the front cut about even with the back of the cage and the rear cut at the lower crossmember behind the rearend housing.

I would put a left bar in that was bent (or "V"ed) to lower it an inch or so lower that it currently is right under the rearend housing. For the right side, put the outside of the new tube against the inside of the original tube to move the bar over.

JMO,
SPark

[dirttrackrocker]

I agree with LM14 Andy... My new car is under rail also. If it is hitting under acceleration, you are losing a ton of drive. Chop it out and put a bent piece in. This is gonna be worse now that you got rid of the powerglide and went to a Bert. Your acceleration is gonna be much quicker, therefore your suspension is gonna max out quicker.