Technical Cowl Exiting Steering Box Help for Track-Style Build

That would make sense; I thought it strange a 2002 wouldn't have rack and pinion.

 

You will be forgiven for that question [because this is the H.A.M.B]
It is not the year but the model that preceeded the BMW 320 [E21] [E30] and [E36]

Here is a BMW 2002 [1966-1977]


Here is a BMW 320 [E21] 1975 to 1983


Some early E21's have a steering box [later ones were R&P]

 

Also consider a Type 1 VW Beetle steering box [it won't need reversing]

This box clamps around the upper torsion tube [ a bracket with a 1/2 or full round tube could easily be fabricated

The pitman arm has a Keyway and clamp. [not tapered] so it can be flipped around


If you need to move the steering to the centre, cut and clean up the pitman and weld an extension tube to it.
If you dont, just cut off the unused tie-rod lug

 

Big 10-4 on that crummy pitman arm, we changed that out, and if I had overs, would use a 40 Ford wheel but thought quick release needed for entry/exit. This car steers VERY easily.

 

I think the VW setup is the winner for price, availability, and ease of building. The ease of removing the components is also nice with the straight splines, pinch bolts, and set screws. The box is compact too, which will help with legroom.

Looking online, the VW box appears popular with the dunebuggy crowd, so parts are plentiful. I can get a rebuilt box for $90, the housing clamp for $20, and a used pitman arm for $30 (even cheaper if I come across a complete unit at the junkyard). The input shaft coupling is $15, and another donor steering box (likely a 70's/80's metric GM for aftermarket pitman arm selection and junkyard availability) is $35 at the pick-a-part. Throw in $15 for a remnant piece of DOM and tubing for the box mount and the setup comes to about $200.

Here's a quick drawing I made as a brainstorm:

 

Early 30s GM pickup box worked for me and a couple others. Also, 60s Mopar boxes work well, they come in steel or aluminum

 

So, basically you are looking for a manual box with a long sector shaft to reach outside the cowl? Have you looked at F-150 boxes (about a foot from wormshaft to pitman)? Lots of 50-60's boxes had long sector shafts.

On my project I used a late 60's Mustang box, but it needed the sector extended (machined and welded) which I did with the help of a machinist friend. I had to reverse the box to get the pitman pointing down. And we built a pillow block to support the long end of the sector, bolted to inner bracing just inside of the cowl skin.

 

Correct, the output shaft needs to extend from the box centered on the column to outside the lower cowl of a '26 Model T. One issue with using pre-1970 boxes is that local availability at decent prices is drying up. It's rare to see a pre-1975 vehicle in my three local pick-a-parts. Then people on eBay think anything pre-1970 is made of gold, and between the price and shipping it would be cheaper to buy a new reversed Corvair box and build an extension. The other issue with 50's and 60's boxes with extended shafts is their housing size. They are a big chunk of steel taking up a lot of space in a Model T that already doesn't have enough space. If one doesn't want bump steer and doesn't want an abnormally long pitman arm--neither of which I want for both safety and aesthetics--the box needs to be nearly on the floor for proper geometry using an approx. 8" pitman arm from my mock-up. The VW box looks compact enough to put down near the floorboard, and the DOM extension would likely be 1-1/2" - 1-3/4" o.d. versus the 3" - 4" o.d. of a 50's/60's F150 or other housing. Not having to reverse the box is another boon to the VW box.

 

Buddy is mounting a older jeep box on my A on B rails project... the pitman arm points up , reducing bump steer as the draglink is closer to level... rugged... made by Ross...

 

Post photos when you have it setup. You might want to read up on steering geometry and bump steer before your buddy proceeds (see the thread link in post #4 that contains a ton of info). I'm assuming you're running a single-connection radius rod or split wishbone in what I'm going to say: The draglink being at an angle or level has no impact on bump steer in and of itself. It's all about the relationship of the pivot points. In many cases with cowl steering on a highboy setup, the drag link will need to angle up toward the steering arm on the spindle at a significant angle (see the screenshot below). While it's more complicated, the summary is that the draglink connection on the pitman arm should be as close to the same horizontal and vertical planes as the radius rod connection on the chassis. An ideal setup would have both pivot points in the same spot. See the photo in post #12 for an example of a setup that won't have bump steer or at least not noticeable. See the photo in post #24 for an example that will have bump steer beyond what is desirable. I don't mean to call out Ron or his ride. I'm just pointing out that physics dictates the #24 setup with the draglink pivot point so much higher than the radius-rod pivot will inherently have bump steer. Even the champ car in my original post would have had bump steer, but not much.

I pulled these resources from the link in post #4. The first screenshot is from the Pete and Jake catalog. Example #2 will have minimal bump steer but still some. Example #3, which is what I read as you referring to a "level" draglink will have bump steer.


Here are some basic videos demonstrating the physics. Don't get distracted by the awesome music.

 

Schroeder boxes are perfect for this (its what Im running on mine)...but they're getting really hard to find. KSE and Sweet Manufacturing also makes sprint boxes that work but are really pricey (1700+)