Thread: 28 Model A coupe steering setup help needed

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Hi, I recently bought my first rod, a 28 Model A coupe. It's a mid 80's build with a TCI frame, and a super bell front axle. I am currently sorting out a lot of bugs on the car that were not done by whomever built it. My current problem is steering.

The TCI frame has a mustang steering box set - up with a drag link to the steering arm on the left spindle. Initially the pitman arm was hitting one of the 4 link bolts when turning left. I put a slight bend in the pitman arm to solve that clearance issue.
Here is the main problem

After centering the steering box and the wheels and putting the components back together the car turns faster right than left. It takes 2 turns left to hit the stop but only 1 1/2 turns right with the tie rod actually hits the 4 link mount on the right side. What needs to be changed to correct this ? It's like the ratio is slower turning left and faster turning right. Does this have anything to do with the arm that the drag link connects to being incorrect? Any help would be greatly appreciated.


Here is some more info, the car has a Super Bell standard axle , TCI steel four bar radius rod kit , 1937-48 Ford spindles , 1942-47 Ford Kingpin Kit, TCI steel steering arm, and a 1970 Mustang steering box.

I was looking at this website, is this the part that might cure the problem or is all this normal having it takes more turns left than right?

http://www.speedwaymotors.com/xq/asp...qx/product.htm

With the wheels straight ahead the pitman arm should be in the middle of its travel as well as being at 90 degrees to the frame on the Model A. (Deuces will be slightly different due to the stock 2 degree frame kickup.)

Do your wheels steer equally sharp in both directions?
Or could you have different length stop nuts on the spindles?

Sounds to me like you need to re-orient the pitman arm on the steering boxes splined shaft and adjust the length of the draglink.
It's possible you may run out of adjustment length depending on which way you go.
Custome length draglinks and tie rods are available as well as being easy to make.

Make sure as well that you're not bottoming the steering box out on the internal stops.
That's what the spindle stop nuts are for.

Hi, I added to my first post, maybe that extra info will help. Currently the car does not have steering stops on the axle. Where do I find those or info on how to build them?

So you think My drag link may be the wrong length ? I can center the wheels and center the steering box . The box is 4 turns stop to stop, so I will set it in the middle. Maybe I will go take some digital pics and post them. I really want to get this sorted out as this sort of thing bugs me. I'm not sure what you mean by having the pitman arm perpendicular to the frame, do you mean the actual frame or the steering box mount? Thanks for the help so far

For the most part Model A frames are flat.

So let's assume that the car has no rake and sits level.

Orient the wheels to the straight ahead position.
Disconnect the draglink from the pitman arm.

Center the steering box by making note of the input shaft's turns.
Don't use the steering wheel to center the steering box, it may be off level horizontally speaking - and is one of the last things you adjust.

If the pitman arm is straight up - or down, depending on the steering box in use - with the steering box centered you should be able to connect the draglink with no problems.
If not, you'll have to re-orient the pitman arm to the vertical position. It can be off a bit, but vertical is what you should shoot for.

If the draglink cannot be installed due to incorrect length - either way, short or long - you'll need a new draglink.

The upper steering arm shown in the Speedway Motors link won't cure the problem unless your upper steering arm is considerably different. Perhaps custom made with the tie rod end (or Heim) connecting point off center.
It shouldn't be a problem since most upper steering arms are made with the tie rod end connection point in the center.

Do you have both spindle steering stop nuts installed?
And are they the same length?

Lastly, did you use the steering wheel to center the box?
As mentioned, if the wheel was simply plunked on in the horizontal position with no regard to having the wheels in the straight ahead position, then it's possible that could be the cause of the differing ratio's from left to right.

Ok , here is what I have done....I centered the steering box so it is 2 turns either direction, I did not use the steering wheel as a guide because I will have to re-center it when I'm done curing this problem. I installed the pitman arn so it is vertical or 90 degrees to the plane of the frame. I adjusted the drag link so the wheels are centered. so now the steering box is centered and the wheels are centered. I still have 2 turns left and 1 3/4 turns right. When I turn right the tie rod hits the attachment for the four link, before I make it to 2 full turns, so there is something causing the steering to act quicker to the right. With the drag link unhooked I have equal travel left and right. The are no steering stops installed on the front axle, the previous owner never installed any.

When I looked at the upper steering arm the attachment point for the drag link is about one inch ahead of the center point of the king pin, so am I correct to assume that if I change the upper steering arm to this;

http://www.speedwaymotors.com/xq/asp...qx/product.htm

it should make it turn and equal distance left and right ? There should be no reason to have the attachment point of the drag link to be ahead of the center line of the king pin, correct?

Here are some pics of my car as it currently sits.

http://coogan.efirehose.net/car/steering1.jpg
http://coogan.efirehose.net/car/steering2.jpg
http://coogan.efirehose.net/car/steering3.jpg


Where do I buy or install steering stops? and how are they attached? Thanks for the help so far

A steering stop is an acorn-shaped nut that screws on to the kingpin retainer. Just about any shop will have them.

I'm pretty sure your problem is lack of a steering stop.

Looking at the photos it looks like the front wheels are turning too sharp.
Convenient when driving, but hard on the steering box if it's coming up against an internal stop.
That's also the reason your draglink is hitting the batwing (where the four bars bolt onto the axle.)

You can buy steering stop nuts from most all the rod shop suppliers.
Best bet is a stainless pair.
That in case you have to trim them to length.

The steering stops on my 32 were too long at first, but I didn't find out about that until I started driving it.
I ended up cutting it down in a lathe twice.
After the first try it still didn't run sharp enough.
2nd try was right on the money.

Due to the angle involved a little bit of material removed from the steering stop goes a long way.
I believe I trimmed it 1/16" each time for a total of 1/8" removed ending up with the steering stop 1 1/4" long.
There is a 1/8" thick washer underneath making for an overall length of 1 3/8"

The steering stop nuts on my under construction 31 roadster were 1 1/4" long to start with and the washer is 1/8".
It should turn about the same degree of sharpness the 32 does.

You can also make steering stop nuts from Chevy mag wheel lugnuts.
Get stainless ones so you can trim them down to the right length.
(The kingpin lock bolts and steering stops are 7/16-NF as are the Chevy lugnuts.)

Buy a pair of cad plated hardened washers.
They will look fine with the shiny and polished cutdown mag lugnut.
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Nice front end Henry.
Good combination of chrome and paint (or powder).

You were right on the money. I spent the day fabricating and installing some temporary steering stops. I have equal amounts of travel on the wheels either direction. The steering wheel turns 1.5 turns in either direction from center before hitting the stops.

Is 1.5 turns enough ? ( 3 turns stop to stop )

Now I realize I put a bend in the pitman arm needlessly now that things are set right. I geuss I'll have to buy another straight pitman arm because I ordered some 10 series smoothies from wheel vintiques with a copius amount of backspace. I needed more backspace because the current rim/tire setup is hanging out too far past the fender. Now I'm a little worried the new rims will hit the draglink in a hard left turn. Hopefully the combination of a steering stop and straight pitman arm will give me enough clearance.

Here's a pic of the car , as you can see the rims don't really fit the car , both in size and style. It's kind of got an old school look so I'm hoping the chrome smoothies will be a better look for the car

http://coogan.efirehose.net/car/28ford1.JPG