rack and pinion used with i beam axle..?heard there would be bump steer?

Gary, I will look around and see if I have anything showing the front axle in particular.

 

Here's a couple (not my car) SORRY for the huge pix!

 

Back in the 80's I had one, a axle with a K car rack and pinion, the rack and pinion were mounted to the axle and a GM slip joint, coilovers and a 4 link, worked great, and don't for get you have to use a pan hard bar, and yes I would do it agine.

 

if you have a rack that steers from the middle like the ausi camera or the dawoo lanos you use long equel length tye rods you wont get bump steer i drove a mates 32 blown 32 roadster on one of our goat tracks the government call state highways and gave it abootfull and no bumpsteer let go of the steering wheel and stood on the brakes stopped in a straight line i was very impressed

 

The car left yesterday but will be back next Saturday and I will put it on the rack and take some shots and put on this post.

 

It's really immaterial whether the tie rods attach to the middle or the ends of the rack; if it's attached to the frame you will get bump steer. More strictly, you will get toe changes rather than bump steer, as the movements of the left and right wheels will be in opposite directions. You might think that the movements will therefore cancel each other out, and given a perfectly flat road and perfect 50:50 side-to-side weight distribution they will. You'll very seldom approach those conditions, though, and if they get really bad chances are they'll go bad quite suddenly.

I don't like racks riding on axles, but I can think of at least three other ways to use a rack and pinion with a solid axle without getting bump steer or toe changes:

1. Mount the rack alongside/below the driver's side frame rail. Run a drag link from the end that's pointing forwards. You'll need a seriously u-jointed steering column to get to the resulting pinion angle, but it's quite practicable.

2. Mount the rack on the firewall, above the bellhousing. Run a short link to a bell crank with a vertical shaft, and a drag link from that: or mirror the entire mechanism for a double drag link/no tie rod system like on Foose's P32. This will allow a very short, straight column, possibly without more than a single u-joint.

3. Mount the rack vertically on the firewall, with a short link from the bottom end to a bell crank, and a drag link from there. If you play with the rack angle you might be able to use a solid column with no u-joints at all. It'll be short enough to be safe and reliable.

In all cases the same rules apply to locating the rear end of the drag link as do for a steering box set-up.

 

Handles like a slot car.
Just got back from a 3600 mile road trip with no issues @ all

 

Lots of good posts and input. Had a frame mounted rack from the previous owner. Liked how easy the wheel turned and the install was good, but not the exact geometry to eliminate bump steer. The plan was to layout a way to both look good and operate correctly. Final result was building a cross steer setup with a vega box. Some might say cookie cutter, but it works quite well, no more bump steer and looks clean.

 

Anybody done an axle mounted rack on a parralel leaf front end?

That would pose some issues with more fore/aft axle movement than a hairpin set up, i'd assume.

LOT's of good info from you guys!

-rick.

 

A friend of mine had it done with an Anglia he built. The car ran a built 440 Mopar and a 4 speed. It was the first time I had ever seen it done and it worked great!

 

KKustomz.please post some info on that axle you built. Thay concept has some many possibilities.

 

Way cool pix. Thanx for posting. I've never been to a modern super race but it's on the bucket list. They are such amazing cars. But it seems the folks that build and race them are in some sort of secret society - crazy and super fast only apply within types. I literally never hear of where they race, when they race, how they are designed or who builds and drives them. Gary

 

X2 Did the same thing in the 70's on a t bucket, pinto rack and flex shaft, they were either only used on automatics or 4 speeds can't remember which

 

Probably the wisest statement on this thread.