questions about my model A rear spring setup

There's your problem. The torque action/reaction pair wants to rotate the ch***is around the rear end housing, which would lift one wheel and load the other. In a properly designed system free to articulate it would do just that. Your can't, so it doesn't move. It's that characteristic which makes ladder bars work well on the strip, but lousy on the street.

Bob

 

When I was mocking up the rear suspension in my A coupe (using a '40 front spring, with leaves removed) I had hardly any movement in the spring pack, almost like it was rigid. I took the spring apart, cleaned each leaf and rounded the ends, oiled it all up and put it all back in and was shocked at how freely it all moved.

 

chop32. im almost thinkin this too because i painted the springs top and bottom and then put it together,no grease at all.

bobscogin- yeah that would tend to lead toward the spring.not the bars.as i said jumping on it the spring doesnt move much

 

"do you guys take out a lot of the top small one? "

Taking the top short leaves out has little or no effect on the rate.
It only helps reduce the height of the spring pack itself.
The long leaves like the 2nd, 3rd and 4th are the ones to play with.
Be SUPER SURE the top leaf that fits in the cross member is rounded on the top edges to fit the cross member perfectly...Very important.

 

looks like i have about 6 counting the small top one.i heard about cutting grooves in the spring the length of it to relax the spring a bit.

 

heres my rear spring,best pic i could get. looks like i left the first spring after the main in it,possible took one out after that,left the next,i cant see how many is in the top,nor do i remember how many i took out, i think i removed 3?

 

should i try to remove that one right on top of the main? i heard to leave it since it helps the main from stress and if i removed it the main could snap?

you can kinda see up in the pack in the other pic the medium leaves,theres a few in there

 

I don't have an "A" spring on the floor right now to give you an accurate count of which leaves to pull and which to leave. Pete1 above is correct in his ***esment that you don't just want to run all long leaves. Start out with the main, then pull every other until you get to five. Try that, and if it doesn't ride well enough for you pull on more.

Now, as important, you have to take some time to round the ends of each of the leaves. Just grind a nice radius on each to keep it from digging into the next one down. If you don't do that, by the time you clamp the springs, they go ridgid. I also LOVE teflon between the leaves. Not super traditional I know, but it works really well, isn't a mess and can be easily hidden with vinyl friction tape or even better a large piece of shink tube.

 

i think i did grind all of the ends of the bottoms smooth when i took out my last leaves. i think i took out every other leaf to,but i left the one right on top of the main,i then removed the next one,and alternated after that. im almost possitive i took out 3. cause i cut them in peices to add to the clamp so it would tighten.

i know my rear end is perfect setup but i think a change in the leaf will help it. ive seen a lot of rear setup hardmounted at the axle like mine.

i shouldnt remove that one right on top of the main should i?

 

As much as I respect all of you guys opinions about split bones on the rear being his problem, I have to disagree. I've owned a few cars with split bones and hairpins on the rear that are mounted to the sides of the frame and none of them have handled badly. If you look at the thousands of cars that are using them that way all of them can't be ill handling or people wouldn't be doing it. Every time I drive my 27 I comment to myself how nice the ride and handling are, it even amazes me.

My current 27 has exactly the same setup as the OP, except I have hairpins, and my old 23 had PSI split bones on the back, and both of those cars ride very well. The stiffness he is complaining about is not when one wheel is trying to lift, it is when the rear is bouncing up and down.

One thing he might do is dis***emble the spring and put teflon ****ons designed for that purpose in between each leaf.

Don

 

^ thats what im saying don, its not side to side bind, i know its there,but its not what im complaining about. its up and down like you said. i agree with you.

 

In the last pic it looks like you have only one
bolt holding the rod to the axle.If so stop
driving it its a death trap
the spring in the rear is stiff beacuse the
axle can twist and bind the shakles
you have to mount the rod to the axle
with two bolts or some other way so
the axle could not twist even if you
take the spring away

 

The only things that can cause what you and I are talking about is:

1) Too stiff of a spring

2) A spring that is binding and the leaves not sliding on each other.

3) Too stiff shocks.

Here are the slider ****ons I am talking about, they come from a company called Ch***is Engineering INC, not to be confused with Ch***is Engineering.

http://www.ch***isengineeringinc.com/page7.html


What you do is drill a 5/16 hole in the end of every leaf (except the main leaf) and you insert these ****ons into those holes, sandwiching them between two leaves. They go on the ends of the leaves and sort of create a Posies Superslide spring from a conventional spring. I have used them and they work great, but you will burn up a few drill bits drilling the holes in that tough spring steel.

We used to try to do the same thing by cutting strips of window screen and putting it between each leaf, and packing it with grease. Then we would tape over the whole thing with electrical tape to keep the grease in. It did help, but then places like Speedway came out with their strips of plastic that you cut and put between the leaves. I have tried those and don't like them because they wrinkle up on the edges and look goofy, but I guess in function they are ok.

Don

 

Absolutely what I was trying to say Don! I do know how "wrong" splitting a pair of rear wishbones out the frame rails is, but damnit, it's been done a million times for the last 65 years or so. Truth be told, it works ok most of time. The only thing I have had problems with in that case is cracking between the mounting holes on the axle end of the wishbones. If you keep an eye on that, it's all good. I too believe that his troubles are in the spring it's self, or the shackles and their angles. The other thing I can think about at this time too is a bit hard to explain, but is the rear mounted in a manner where the wishbones are perhaps a bit short? Visuallize it from the side as the top of the spring being pushed just slightly to the rear.

As the rear end pivots on the front mounts of the wishbones, it makes an arc that just slightly moves the rear end forward under compression. If the wishbones are adjusted a small bit short, the spring can be coaxed up into the crossmember, but it is in a slight bind fore to aft. Not real common, but I have seen it happen before.

Just something to think about.

 

theres two.thanks for calling it a death trap, its been drivin many miles. with only a stiff ride to complain about.

 

Precisely. I too was wondering about the length of the wishbones. Too short would cause some bind.

I found this picture of when I mounted the slider ****ons on the springs in my 23. For a buck a piece they really do a good job, and come in two widths, one for the narrow front spring and one for the wider rear spring.

Don

 

i like these,yeah pretty much making it a possies. thats a cool idea

 

YES! it does slightly try to crack between the two mounts on the wishbone but i welded the hell out of it and it seems to be holding up

 

If you do it, buy a few high speed 5/16 drill bits. No matter how you lube them they burn up trying to go through those leaves.

Don

 

also my wishbones are VERY long. i heard that helps in some of the side to side,they go about right under the middle of my door.

im wondering tho,should i try a t spring?

 

I've never been too hip to drilling holes in my leaf springs, but out at the ends probably wouldn't hurt. Once again you could easily hide it with tape or shrink tube. If you have to drill, an old buddy of mine years ago taught me to use white glue as a drill coolant/ cutting aid when drilling spring steel... Sounds completely rediculous, but it works like a charm!

 

A "T" spring is a 1/4" narrower (2" versus 2 1/4"), so you would have to space it at the shackles. Generally, it will lower the back of the car a bit (Depending on what "T" it was made to fit), but I don't believe that it will really improve your ride quality right out of the box, so to speak. Personally, I'd spend some time making what you have that fits the car correctly work to it's fullest.

 

The nice thing is that each successive leaf covers up the hole on the leaf below it.

I found this picture of how we made the radius rod mount on my 23. We knew there would be forces trying to dislodge the radius rod from the housing, so we over engineered it. It is gusseted to hell and back.

Don

 

louvers-these are the reasons im on this site, old tricks are the coolest things to hear.

i kinda want to try and remove a spring and grease them first,its just tuff since my pipes are in between the axle and leaf.my whole exaust has to come loose to slip the axle out.but ill get to it soon i hope.

i might try a t spring tho since they do not go on under tension like the A spring does.

 

don,looks like we have about the same number of leafs.

wich ones should i remove? i do want to take more out.

 

Just a quicky. When I do run a split wishbone on the rear, I always mount the axle ends in double shear (Plate on the inside and outside with mount holes). If there is a chance of stuff cracking, at least it can't go anywhere.

 

i see, i built mine after a really old school design. a kind of 1/4 dog bone shape welded to the rear and the same welded to the wishbone,then 2 bolts. mine is not sandwitched so to speak, i found after a year on had cracked and the other started to,but the rear end was still hangin on,it cracked cause the bracked i made was too small in between the two mounting bolts, i v-ed it out and did about 4 wide p***es of weld on them.so far they seem to be holding.

if i had the room and extra money i would 3 link it.but also i like the traditional look of what i have,it kinda fits with the f1 box i modified with A flange. i think its cool to be at a car show and even most of the old guys with their plastic 32's dont realize its kinda the way it used to be done

 

Hehe! Couldn't help but smile. Maybe it's a reflection of our age differences or regional differences, but when we were kids, "Jumping on it" meant accelerating hard!! Interpretation is everything! Anybody else ever use the phrase that way?

Bob

 

Looks like the spring eye is touching, or really close to touching the axle in this picture. . . that would keep your spring from having any "bounce".

Might also want to put a gusset on the outside of those mounts. If they start to flex they'll eventually break off.

 

That looks like a pretty steep angle on the shackle. If the eye on the spring is too close to the axle housing it could hit when under load. It should be at 45degrees when the spring is at rest.