Radius Rod Question

[jimbo01]

Hello Everyone,

I'm questioning my placement of the radius rods. In following Youngster's plans I placed the radius rods just outside the shock mount but I can see stress on the clevis'. The radius rod measures around 8" from the kick up and then again around 8" to the fiberglass bed. Did I misplace these brackets or do I need to bend the bracket to relieve the stress from the clevis'? In one thought It appears the radius rods seem to stick out of the body to far and makes me question tire & exhaust clearance as well.

Thank you all in advance.

Jim

 

[railroad]

First most builders have more experience than I do, but the location on the axle looks ideal. The angle of the bracket should be the same as the radius rods as they go toward the axle. It looks like the brackets are square to the axle tube. I am sure you will get more advise on the placements.

 

[ellis8500]

The axle bracket needs to be at the same angle as the radius rods, not perpendicular to the axle tube. As it is now, the clevises will fail quickly.

 

[RPM]

We put the rear brackets just 3" from the frame and shock brackets out side of that. Too much stress on the clevis will cause them to break. At this point I would just heat those brackets and bend them in some, to get everything straighter.

 

[Youngster]

For those who are about to tackle this part of the chassis build, assemble your hair pins to the batwings before you weld the bracket to the axel. The bracket and hairpin will run at an angle to the frame rails. Heating and bending the batwing bracket is the only way short of cutting it off to correct this.

Ron

 

[jimbo01]

Update:

I've pulled the batwings off and am ready to tackle it again. Now I have a couple of options as far as remounting. Ron's suggestion was to mount it at 3 inches from the frame. The problem I have here is I can't because of the lower shock mount is in the way. I can however mount it on either side of the shock mount. One side (closest to the frame) the measurement will be 2 1/2 inches or just inside the mount and would be 3 1/2 inches. Any suggestions would be greatly appreciated.

Jim

 

[Mr T Bucket]

Cut them all off, shock mounts and radius rod mounts, and start over. Steel is easy. Cut, grind weld, cut grind re-weld if needed. Move the lower shock mounts farther out towards the wheel, and move the radius rod mounts in. You'll lay the shocks down a little more, but I think it looks better than straight up and down, plus it softens the ride a bit due to changing leverage angles and fancy engineer ciphering applied to the published spring rate. Tack weld, size it up, measure it out, check for suspension travel and any issues with the radius rods hitting the body. Figure about 3 inches up and down for the rear axle. Doubt it would move any more than that, if that. When everything looks good, finish welding it up.

 

[bigfrank330]

Hey on the one I just finished rebuilding and the SPIRIT I am going to start building
The shocks were outboard toward the brakes and the Radius rods are inboard towards the center of the axle
They are right next to each other
Reverse them and you should be good
Frank

 

[Youngster]

How wide did you make the frame? If it's 23" wide as per the plans your shock should be at a 60 or so degree angle. If you made your frame wider, move the shock and hairpin out tward the axle ends accordingly.

Ron

 

[jimbo01]

Ron
I made the frame 26" wide and shocks are set at 20 deg.

 

[Youngster]

Most coilovers come with 140# springs. At 20 degrees just opt for some lighter springs and you'll be good.

Ron

 

[jimbo01]

Where would be the best placement for the batwings at this point? I really hate the idea of trying to get the shock mounts off.

 

[RPM]

Update:

. One side (closest to the frame) the measurement will be 2 1/2 inches or just inside the mount and would be 3 1/2 inches. Any suggestions would be greatly appreciated.

Jim

I'd go ahead and put them at 3 1/2" and line up the rods with it all.

I am just concerned about all this welding heat on one side of the axle. It might warp the tube! How did you go about getting the bat wings off, after they were welded on?

 

[Youngster]

What Ron (RPM) said ....

Ron

 

[Ted Brown]

When welding the RR brackets to the housing (after tacking & lining every thing up) I make a back half circle, about 1/2" wide that fits the housing, this makes the weld go completely around the housing, keeps things straighter and stronger as well... Don't forget to install bump stops so that the movement will not go beyond the safe operating angle of the U-Joint, too far and the U joint will fail... The shocks should stop the housing from dropping to far down and causing the joint to fail from that direction, other wise a safety belt strap setup will keep the housing from dropping to far. I happen to use rubber bump stops at both the top and bottom on my rear end... BTDT not fun when a U joint brakes...

 

[2old2fast]

It's very easy to warp an axle tube [BTDT] , however , if you do like Ted said and add extra steel so that you weld all the way around the housing , it "should" help to prevent warpage.

dave

Also, make sure when mounting your RR that far outboard that you'll clear the body...

 

[jimbo01]

Well, I got the RR brackets of without much trouble. Just took the grinder and cut through the weld and tapped the RR bracket with my hammer. It was a slow process but all is well. I did reinstall them and closer to the body. The are now around 5" away from the frame and centered between the shock mounts. I Like the flow much better now as they follow the lower body line. I didn't like the location they were in the first run due to obvious reason and I felt they gave it a combine sort of look. I looked at what Ron Suggested as well at what Spirit and Speedway were offering. I think I got the later and I'm happy with the look and no more stress issues. Pheeeeeeew!!!!!
Is there any examples of these bump stops and safety belt strap?
Today I went at setting the engine and transmission and it was smooth sailing. Now I need to look at how to measure for driveshaft length and work on that next. I think I'm thinking about taking tomorrow off, I'm pooped. But I'll bet I can't keep my hands off the thing, who knows?

I'll post some pic's soon

Jim

 

[cooter]

im about to design my rear mounts like this also. ccr plans say mount coilover brackets at 37" center to center with radious rods moved outside coil over brkts. my frame is 26.5 wide. that puts my coil overs at 5 3/4" from frame on both sides. should I scratch ccr plans and follow Rons plan?

 

[cooter]

ccr is showing rr hangers at 45" apart with the two rr mount holes 90 deg. to ground?

 

[RESINATOR]

Here is a photo of the rear end set up. The further the brackets can go out the better.