Need some input here. I'm going to use a '48 Ford cross steer box in my Model A AV8 project. Where I have it lined up on the frame, the drank link is not parallel with the tie rod. The drag link coming off the pitman arm is probally 30 degrees apart from the tie rod at the furthest part from each other. Is this going to cause a bump steer or steering problem? I'm thinking that I've read something that the drag link & tie rod rod should be parallel or close to it. Thanks for any advice.
I heated & bent my pitman arm up so the drag link was paralell with the tie rod connecting sleeve, no bump steer, sent the pitman out for magnafluxing afterwards just to be safe.
If you search for cross steer you will get some good pictures of later boxes in early frames. I'm right in the middle of putting a 37-39 box in an A (I'm going to go weld the tabs on in a 1/2 an hour) and you have to mount the box FORWARD in the frame. I'm going to run one u-joint, I have an SBC so it creates a little bit of a clearance issue with the motor mount (flathead mounts are farther forward). As for bumpsteer, no matter whether the box is forward or rearward in the frame, the transverse arc which the pitman to steering arm swings is going to be different than the arc which one tire will swing when you hit a bump. This will cause some bumpsteer. The question is, will it be noticable? Chances are it won't be. An A only has a couple of inches of travel so it's not a big deal. If you do want to mount it back where the side steer box was, you need to check the clearance with the oil pan and you might need to bend the pitman to get the angle right.
Guys, Thanks. Maybe I need to clarify a bit. When looking from the ground or head on underneath the car, the drag link & tie rod will be parallel. The 30 degree difference is if you were looking down into the engine compartment. The 30 degree differences in angles is from the drag link coming off the pitman arm to the drag link. I hope this makes sense. So from what I read, keeping the drag link & tie rod parrallel to each other & the ground is the key here correct?
Yes.....you don't really need to worry about the 30 degree angle of the drag link to the tie rod bar (overhead view). That shouldn't effect the bumpsteer. The transverse distance (width of the frame) side of the triangle stays the same (roughly) if the box is mounted forward or back. And you want the drag link to be parallel to the ground.
The old survivors that I've seen with a late 30's-40's column and box had the drag link angle you speak of when looked at from above and must have worked fine. That's the only way I know of doing it unless you cut the box off and add ujoints and shafting to get the box closer to the tie rod. That's the way they were.
Guys, Thanks! I was hoping to NOT have to add steering joints. This solves the issue at hand. Back to fabricating!
The Jalopy Journal
