Model A rear spring hangers

Hi

I am a new ”member” with an urgent question.
I am building a 29 highboy roadster on 32 frame rails.
I am using an original model A rear spring on a Winters quick change rear axle.
Before I weld the spring hangers to the rear axle I need to know the distance between the spring perches on the (original) model A rear.
I was informed that the distance is 49 inches but I need to know if that is correct.
I think that 49” is to far apart to make the stock spring function properly.
Need your help as soon as possible, need to get this chassis rolling soon.

Vegard

I have an A spring on the rear of my rod, and don't think it is 49 inches because I am using an S10 rear and they are only 49 inches backing plate to backing plate,and I am inside that. I also have one under my '27 and can measure that one for you, but I won't be back home till Sunday night. If you haven't gotten an answer by then I will measure both for you and advise.

What you want to do is measure your spring at rest, then add about 5 inches. 3 inches will be taken up by the shackles, which allows another inch per side for the spring to get stretched out so the shackles lay on a 45 degree angle when loaded. My spring has settled since I have been driving the car, so my shackles are not maintaining that 45 degree angle any longer. I may have to buy a new spring or at least have a shorter main leaf made up, which I did on my '27.

Don

It looks like this is your first post so let me welcome you here - and I hope that you check in regularly. I even know where Trondheim is, having been there once on business about 20 or so years ago.

Your question - you are correct that 49 inches is too wide but unfortunately I can't give you much more then the width, unloaded, of the Model A spring should be - and that depends on the number of leaves, 7, 8 or 10 and the car model. It varies from 37 7/8 to 40 3/16, C/L to C/L of the spring eyes.

Hi again

Just went to a member of the veteran car club and measured the rear axle on his 31 coupe.
It measured 49 ¼ inch C/L to C/L of the spring perches.
This will give me a problem because my rear axle housing is only 51 ¼ inches.
I am using Wilson Welding finned aluminium backing plates.
Distance between the inside of the backing plates are 47 ¾ inches.
This makes the maximum distance C/L to C/L of the spring hangers to be about 46 inches.
My stock 7 leaf Model A spring is 40 ¾ inch C/L to C/L of the spring eyes at rest
If I follow Dons advice of adding 5 inches to that I end up at about 46 inches witch is the maximum distance possible between the spring hangers:)
This turns out to be more luck than engineering.:3dSMILE:
I will mount my spring hangers 46 inches apart.

Vegard

Keep us up to date and post some pictures as you make progress.

You might want to consider removing a leaf or two if you are building a fenderless high boy. Model A Fords had the ride of a brick in their original form due to the poor roads of that period:3dSMILE: .

Does the Winters unit include better axles than the stock A rear?

Don Shillady
Retired Scientist/teen rodder

As I recall there were several different Model A springs and the high arch one that is in the Speedway calaloge is much stronger than the almost flat spring that was stock on the original roadster model. Of course you need to space the shackels for the spring you use but you might consider removing one or two of the small upper leaves for a better ride. A lot of modern rods have a Ford 8" or 9" but that pumpkin looks dreadfully plain compared to a banjo quick change. You can't even put a dress up cover on the 8"/9" so on my 8" all I did was just paint it black! Some folks frown on the use of a "fake" quick change but if you have a real one you should flaunt it!

Don Shillady
Retired Scientist/teen rodder

As I mentioned in my earlier post, I had a shortened main and second leaf made up for my '27. I just took the stock leaves to a spring shop and told them "make me one 3 inches shorter." That was an easy one day fix. 20 years ago I paid them $ 18 to do it, but I just did the same thing on my '39 Dodge front spring and it cost $ 120 this time!! :eek: But it solved my problem, so it was worth it.

Just a thought.

Don

Quote:

---

Originally Posted by Don Shillady

Does the Winters unit include better axles than the stock A rear?

Don Shillady
Retired Scientist/teen rodder

---

The Winters quick change axles are significantly stronger then the stock A's

Hi all

I am planning to remove 2 or 3 of the upper leafs and if the stock spring don’t work out I will have a new made up according to my specifications.

The Championship Winters quick change is strong with a 10 inch ring gear and 31 spline Ford axles. Maybe overkill in a light roadster but I`m running a 452 Hemi………..:toocool:
See link below.

http://www.wintersperformance.com/ca...ars/021024.htm

Vegard

Hi all

I am planning to remove 2 or 3 of the upper leafs and if the stock spring don’t work out I will have a new made up according to my specifications.

The Championship Winters quick change is strong with a 10 inch ring gear and 31 spline Ford axles. Maybe overkill in a light roadster but I`m running a 452 Hemi………..:D

http://www.wintersperformance.com/ca...ars/021024.htm

Vegard

Hi

Just last night I found that Posies sell a shortened super slide rear spring for the Model A.
It is designed for a spring perch C/L to C/L distance of 62 ½ inch
This is exactly what I need so I ordered on of this springs last night.
Hopefully I will have it here in Norway next week.

The Winters Championship Quick Change have 10” ring gear and 31 spline Ford Axles.
Maybe overkill for a light roadster, but I am running a 452 Hemi…….:3dSMILE:
I tried to post a link to the Winters catalog here but never managed to do it.
So a picture will have to do.

Vegard

The mounts are, eye to eye, on an A rear end is 46"

Ron

Hi all

Here is finally a picture of the rear axle with model A spring mounted on the frame as requested by IC2.
This is only a mock-up, to see that everything lines up.

I will post more pictures later if you are interested.

Vegard

Hi again

Here is a picture of the car with front suspension, body and mock-up engine.

Vegard

Attachment 31034

Quote:

---

Originally Posted by 452 Hemi

Hi

Just last night I found that Posies sell a shortened super slide rear spring for the Model A.
It is designed for a spring perch C/L to C/L distance of 62 ½ inch
Vegard

---

Looks like you're doing well on your project, just one thing though.

Not to pick nits on you, but sometimes these threads are used for future reference by others. That figure of 62 1/2" for the hangers seems to be a typo. Looking at the way your tires fit to the body and eye-balling the wheel offset, I'd bet your whole rear axle assembly from mounting flange to mounting flange isn't over 57". Could you verify what you ultimately did?

I've got the Posie 29-31 R-C spring and my hangers are 44 3/4" hanger center to hanger center. Sorry I didn't answer your question when you first did the thread, but I was in Vegas and the car is here in Washington.

Hi again

CL-CL on my spring hangers are 46 1/2".

Sorry for the mixup...................:o

Vegard

I spent a fair amount of time around a Model A repair and restoration shop and the one thing I remember about those springs is they wouldn't even attempt to install one without the spreader tool.

Quote:

---

Originally Posted by willowbilly3

I spent a fair amount of time around a Model A repair and restoration shop and the one thing I remember about those springs is they wouldn't even attempt to install one without the spreader tool.

---

I have found the easiest and safest way to mount a transverse spring is to unpack the spring, put a couple big "C" clamps on either side of the center bolt, than remove the center bolt and replace it with a length of "All Thread rod" and some big fender washers and tighten down, Remove the clamps and slowly run the nut off the all thread, watch closely to make sure none of the leafs in the pack are walking out to the side,.... as you loosen the nuts the pack will relax and the tension will come off the spring,...... mount the main leaf, which now can be done by hand,.... (than basically you just reverse the procedure) and using all thread rod, big flat fender washers, an being careful, you just tighten up the nuts,.. ( again make sure the pack leafs are going together straight and none are walking on you ) when the pack is compressed, take two big "C" clamps and put one on either side of the center bolt,..... take out the all thread and replace it with the center bolt,..

I started doing it this way when my spring spreader folder up under pressure with a 32 - 34 Ford curved rear spring on it and whizzed past my head 32 years ago.,..... B.T.W. the spring in the picture is a curved 1934 Ford spring. this process has never failed me.

That's exactly the way I do my springs Highboy. I'm like you, I have a lot of respect for all that stored up energy in a spring. I had a coil spring come out on me one time when I was installing it and it just missed taking my head off. :eek: The clamp/all thread routine you describe works great and is the safest IMO.

Don

I did many a spring that way - back in the old days when I did mechanics for a living (sort of).

Good tip, thanks. I have never messed with those rear springs but have had to improvise on many coil installations.

Does the 32 frame relocate the rear spring behind the axle? My 29 has the spring over the axle?

The short answer is yes. I wouldn't call it "relocate", it's the normal design difference between the two models. There's probably more to this story?

I tried to make a spring with different springs that we had,I ended up buying one from speedway and it worked well, My mount for the spring are way wider then what they were stock, we used a spring spreader. The car has a Pontiac rear end, but I have a franklin 10 inch quick change to put in.