Homemade Ladder Bars and Handling

How are you able to measure the rear steering, if you can induce it to measure it seems like you should be able to see the cause.
You have welded on the rear axle, right? If you welded on the backside of the axle then you may have caused toe-out on the rear end - that would feel like rear steer as one tire or the other had better traction going thu a corner. Have a look at the wear pattern, that might tell you something if you have enough miles on it.

 

Without an overall pic of the frame its always going to be difficult to find the answer

 

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Sorry about not being on point with this thread, work thing.
The axle housing is welded to all the pickup points.
The way I measured rear steer was with the help of my two sons. One leaned the car by standing on the subrail at each door opening while the other held the other end of the measuring tape. I just thought through some possible fault in the measuring due to a minor bumpsteer in the front, which could have possible changed the dimension because we weren't measuring to a stationary rivet or frame bracket point. I chose to measure wheel to wheel.
Tonight, I looked at a 31 A with some crude ladder bars and panhard bar that doesn't have the same driving feeling as my car. The car has a Pinto/M2 front end. The panhard bar length and location is extremely similar to how I built my suspension. This has made me rethink about where the possibility of the problem is. This line of thinking takes me back to the front spring swinging too much between the shackles. I have split wishbones and steer to the left spindle.
http://www.jalopyjournal.com/forum/showthread.php?t=394342&highlight=marmonherrington
http://www.jalopyjournal.com/forum/showthread.php?t=517211&highlight=marmonherrington
Pics of previous three bar which doesn't work correctly and some of my other Qs.
Thanks to those who are trying to help me think through this

 

Let's get back to one of my early questions. What have you done to the front end since it last drove fine? Have you actually done the exercise I mentioned on the front end or are you assumeing it's still just fine because it was once?
The Wizzard

 

PNB, thank you.
The only change I've made to front is to change nut torque on the shackles. I've thought about tightening the left back toward possibly binding.
Rear springs are Afco 23250SR coil over shocks with 250 lb springs at about 12 degrees angle. Fuel load doesn't seem to make a driving change as the 16 gal tank behind the A crossmember is filled an emptied.
Previously, I did correct some drivability by raising tire air pressure, but not on this experiment. I've even went back to the original panhard bar and bracket from my first fab work.
I'm beginning to think toward a front panhard bar or a left dead perch (no fish).
I don't think my car should get so damn upset with a larger road irregularity, compared to what it does. I know it's not going to handle like an IFS car, and I won't make the change to IFS.

 

A front panhard bar will keep the frame from swinging on the shackles and really tighten up the road feel. It made a huge difference on my rod. In what kind of shape are your heim joints? A tiny bit of wear in a few of them can add up to a bunch of free play overall.

Flatman

 

Heims have less than approx 5000 miles and have NO clatter of looseness. Panhard bar and ladder bars are made of 2" x .120 driveshaft tubing.
Again to all that are reading, thinking, answering with thoughts, I thank you.
Pat Moran.

 

The front shackles might be the issue. The shaft that passes through the bushings should have a shoulder on the thread end. The loose side plate should just go against it and the nut hold it in place. There should not be any clamp force on the bushing shoulder and the side plates. In other words, these parts should float not clamp. With the Mustang box and drag link a panhard bar should be optional not necessary. Loosen your shackles so it floats and go drive it. Let me know how that works out.

 

Have been loosened as an experiment. Perches, shackles, bushings, spring, are all low mileage parts/new.
Checking out for the night. Too damn tired from heat and hard work today.

 

Another experiment has led to how I didn't have enough knowledge to place pickup points in a ladder bar suspension.
Lower bar from Heim to connecting is close to 52" centers. Panhard is close to 32" at centers as opposed to the picture and description.
I fouled by having the panhard pivot points being too much off of level. I have cut off and moved the homemade tabs to rotate the ladder bar pickup point to being approx 4 degrees from being level. It didn't look that drastic, but the car driving over a swell in the road feels so much different. My ass doesn't try to hang on to the seat.
It will amaze you by how much rear steer will affect a car on the street like the NASCAR guys will adjust a panhard (track bar) on an oval track.
It will make a car feel like it wants to turn like a turtle diving back into water if the components don't mesh together with geometry.
Think 2 degrees don't make nothin'? I know better.

 

It would probably help you if you answered the questions put to you and posted some pics