Thread: '23 bucket with bump steer

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I have a 23 bucket with T P I body & frame. It has a vega steering box, from the box it goes across to the passenger wheel by tie rod, behind the axle...... then in front of axle it goes from passenger wheel to drivers wheel. Drives good on smooth roads, but on rough roads get some bump steer. It has friction shocks & drum brakes. I didn't build the car. Bought from builder. I was down to Mountain Home Bucket Show & seen a guy with a honda rack mounted in front to the axle. He said it worked great. He didn't know what year rack. I have a picture of his front end. Any body have idea's on how to mount a rack & pinion steering to this.Thanks..........

What your describing isn't really bump steer which is the anomoly caused on "side steer" set ups when the drag link and radius rods move in different arcs during axle travel. Cross steering is, however, susceptible to the axle shifting on the shackles in corners, and that movement is fed into the drag link causing the steering to over react to input. If you're just trying to get rid of the steering problem, why not just install a Panhard rod or a "dead spring perch" on the front axle? That'll stop the lateral movement and eliminate the problem.

Bob

I think Bob is right. I have never been a fan of rack and pinion steering on an I beam or tube axle set up. To work right, they have to move with the axle, and therefore be mounted to it, like the one you described you saw. But they become unsprung weight, and it is hard to get the steering column shaft to move with the axle movement.

I also think they look somewhat ugly on there, but that is just my personal opinion.

Don

Don
how would you use a rack on that type front end would you need a spline shaft and sleeve to alow the suspension to work seperate from the car(steering column)???

My buddy who died a few years ago had a rack and pinion on his T bucket, and it never really worked out well. His was mounted to the frame, which by all accounts is not the way to do it, as the front end will "steer" as the car rises and falls.

As for the ones mounted to the axle, you have hit the problem on the head. How do you make the steering shaft slide in and out of the steering rack as the car bounces up and down? I don't have that answer.

Someone will probably cite that new steering setup where they use essentially 1/2 of a rack that is bolted to the frame rail, and it moves a drag link to steer the car. But that setup is really no different than a conventional box, in as much as it acts to simply move the rod in and out. A true rack, on the other hand, mounts in the center of the axle and acts as the tie rod, except it is controlable with the steering wheel.

I think the fix for jjpop's problem is what bob suggested. Use a panhard bar, or a dead perch to keep the cross steering from moving the axle from side to side.

Don

Don
if you were to use a pan hard or dead perch wouldn't that just try to pull the tierod ends out of the rack as the suspension moves up and down??

No, I meant to use those items with his existing cross steering setup, not the rack and pinion one.

Don

OK I just couldn't get that set up to work in my mind. thanks for setting me right on that. I have never had the opertunity to work on a front end like that so I didn't know.

I've never run a panhard bar and never had a bump steer problem because I always run a Ford pickup steering box with a traditional drag link that runs fore and aft. When I am steering, the forces are straight forward and backward, rather than side to side, as when using a Vega or similar cross steering box.

Everything I have ever heard is that it is manditory to run a panhard or dead perch with these cross steering boxes because of the way they shove the axle from side to side when turning the wheel.

I have also heard that radial tires accentuate the effect because the sidewalls are made to flex. Don't know if that is true, as I always run bias plys. This is one of those subjects no one seems to absolutely agree on, and there are 100 ways to go about it.

Don

Maybe I'll have to build one to play with.

Yeah, it would be a perfect stable mate for the other two you have.


What is it they say about "most toys" and "dying?"


Don

I realy don't want Or need MOST but I do have enough room for a few more projects in the shop. Besides I start getting S/S check here soon I figure I got to keep the econemy going.

I was thinking that a stick setup could be run in a bucket if the engine were a little lower and a little farther forward.

Besides I realy hate building stock just seems like its been done

As far as I'm concerned, the TP steering needs help. I made some significant changes in the car that I built after a couple of years of having it jump sideways off a bump too often. The reversed Corvair steering box mounts under the body and out of sight with the exception of the Pitman arm. The steering shaft is sloppy and is mounted on the steering box input shaft by a slip link, After mine split, luckily while standing still, I changed out the iron box for an aluminum unit that still had a spline. I used a Borgeson U-joint and fastened it rigidly to the steeing shaft and set screwed it to the input shaft. I believe that TP STILL uses that dangerous system, even after Mickey Lauria and I discussed my part failure and a friends.

Secondly, the drag link from the Pitman arm to the steering arm on the left spindle as well as the steeringarm/tie rod are too light - in both diameter,3/4" and wall thickness. If you watch them while driving, they flex and vibrate - A LOT!! I replaced mine with 7/8" Speedway race car pieces. I also replaced the cheap TP rod ends with regular tapered tie rod ends, even though I had to buy an expensive reamer (which I still have). After bolting all this together, a real significant change was seen. Also, at the same time, I replaced the wimpy Hurst/Airhart brake setup with a Wilwood and changed the juice jar master cylinder out to a dual unit - after losing my brakes 3 times when the crappy TP SS flex lines blew out. These were replaced by Russell DOT's.

So, for whatever it's worth, a Total Performance car is still pretty good, it just needs some refinements in some components.

And another item, the TP hydraulic e-brake is by DOT illegal, the mechanical one is OK. TP and I discussed this several times as well - now they have both.

The car has moved on from me - just hope the new owners have enjoyed it as much as I did building and driving the car.