[Slomotion34]

I finally have my front end together and I am having a couple of issues. Here's what I have:

It's a 4" drop I-beam axle with 4-bars. I have a Vega box installed that may have to be moved back - the pitman arm is interfering with the tie rod. My plan is to try a stock Vega pitman arm with the offset in it to clear (the bolt head that connects the rod end to the end of the pitman arm is rubbing on the tie rod). Moving the Vega box back is complicated by the motor plate bracket on the frame.

My question is, how much clearance do I need between the bottom of the frame and the tie rod? I only have an inch right now and that looks like a disaster waiting to happen on the first bump I hit. I plan on notching the frame above the tie rod and drag link, I just have no idea how much a pothole could cause the front axle to move. Other than jacking up the car on one side @ the wheel, is there a better way to determine how much it can move? Thanks!

[Slomotion34]

Here's a pic of the clearance

[aosborn]

At some time (maybe many times) in the cars life, the suspension will move until something hits the frame, bumpstop or the shock bottoms out unless the spring is so stiff that it can't. If you remove the tie rod, determine how much clearance the supension has in bump until the next thing hits, like the axle to the frame for example. If that is enough travel for you then that is how much clearance you need for the steering linkage. I would recommend at the very least 2'' of bump travel before you hit a bump stop, 3" is better.

Andy

[Slomotion34]

Thanks, I'll do that. Exactly what I was looking for!

[Frisco]

Judging from the photo you posted, the steering arms that you are using appear to be the 'flat' style. You didn't specify what spindles you were running. Below are photos of various steering arms for both 49-54 Chevy spindles and primarily for 37-48 Ford spindles. At least one version of the Ford spindle steering arms is a droppped style. The flat style steering arms can also be bent to a lower configuration. This will enable additional clearance between the tie rod and the frame.

NOTE: Early stock Ford spindles, when running a dropped axle, had to have the stock steering arms heated and bent to clear the radius rods.

The photos are scanned from an older Speedways catalog, so I blocked out the prices as they are not current.

I had a similar problem with the mount position of the Vega steering box. The positioning had been done by the aftermarket frame manufacturer. Rather than cut it loose and relocate the mount, I found that their are several different length pitman arms available for the Vega box. I found one that was about 1" shorter than what was on the box when I got it. Problem solved. Steering was effortless.

[Slomotion34]

Thanks Frisco... I have been looking for different length pitman arms, and Speedway just started carrying the stock Vega items, which I ordered to see if it clears. The steering arms are flat (Speedway 37 - 41 style spindles). I considered the 3.75" lowered steering arms, but that puts it exactly where the lower 4 bar is. The "stock" steering arms have a 1.75" drop from the mounting holes, but that pretty much puts them where the flat ones are (although they do look much better).

This is my first build, so I am learning on the fly about this (What can be bent, what can't, geometry of the components, etc) so I really appreciate the information.

Thanks again!

[Frisco]

Originally Posted by Slomotion34

I considered the 3.75" lowered steering arms, but that puts it exactly where the lower 4 bar is. The "stock" steering arms have a 1.75" drop from the mounting holes, but that pretty much puts them where the flat ones are (although they do look much better).

Most of the aftermarket steering arms have the tie rod taper bored halfway thru from both the top and the bottom. This enables the tie rod end to be installed either above or below the steering arm. You may be able to use the 3.75" dropped arms and install the tie rod above which will enable it to clear the lower 4 bar and still give the needed clearance below the frame rails.

Some combination or slight modification will work.