Hot Rods Tranverse Springs Tech Info.

See a note that was made ,said rev.-eye makes spring longer/fact is only thing that matters is how long the spring is in car with full load on it !! So the shakels are about 45*,the rest is pertty don't care as far as spring size other then how they ride
. Axles,Ford 1942 to 1948,are the same really,only in 48 Ford added 2 holes for tube shock near the kingpin lock hole. I like these 42 to 48 axles with factory drop built in. 48 is what I used in my first hot rod build ,I did in 1959. The front spring is custom done from parts of 3 other leaf springs,that I fitted together to make up spring for ride hight an how soft I wished an being out front of axle lets frame be lower plus softer ride . The rear is also set up behind the rear axle for the same thing.

 

Had to do some hunting,but did find rear photo,I took on last restore a few years back. In 1959,I had a 1950 Olds rear an made custom brackets,after replacing that rear some years ago with 64/5 Mustang rear,made brackets a little smoother but nearly the sameway. The WB ended up at 97in. , 1928 "A" {but boxed} frame is stock other then front cross/spring mount is about 2in.s ahead of stock "A"

 

Here is something I found that has been posted before somewhere here on the HAMB regarding rear ends and deserves to be shown here IMHO.

 

With tranverse springs at both ends of early Ford ,the best place to control lean side to side is rear center U bolts,the rear cross is designed by Ford to be wider between ubolts then front. That gives the rear set of ubolts more control of side to side lean,by how they are adjusted.
The front ubolts had less,but do matter.
Split bones/as in how most hot rods are built,act as strong swaybars,vs when they are stock wishbone set up run to center of frame an are not controling lean/sway as split bones do. Back before I retired,I fixed a number of poor riding hotrods that came in for help. I did mostly only race cars in my speedshop "Comp. Tech". Saw many misstakes that I had to fix, from poor side to side WB,Split uneven bones,out of Sq. frame or twisted. Some times just really bad engineering,like backword ackerman, bad cowel steering an alike. Springs were only a small part of bad ride in some,yet can be really messed up as well.
In the late 1960s an through the 70s I was one of only 5 shops in Miami Fla. that rearched spring for race cars.

 

Something I had forgotten about is the mono leaf spring used in the transverse form.

 

What are leaf springs?
Leaf springs are a basic form of suspension made up of layers of steel of varying sizes sandwiched one upon the other. Most leaf spring setups are formed into an elliptical shape through the use of spring steel which has properties that allow it to flex as pressure is added at either end, but then returning to its original position through a damping process. The steel is generally cut into rectangular sections and then once held together by metal clips at either end and a large bolt through the centre of the leafs. It is then mounted to the axle of the vehicle using large U-bolts, securing the suspension in place.

The elasticity of the spring steel allows for a pliancy within the suspension for comfort and control of a car while moving, and a leaf spring setup has been proven as a viable option for cars for many decades, despite only really being found on HGVs and Military vehicles these days.

 

Transverse leaf spring and solid axle front suspension of early Ford cars is a type of automotive front suspension that has been most common in early Ford Motor Company products.

 

Transverse springs found In many vehicles and not just solid axles
Studebakers
Corvettes
GM W body
Iveco
Volvo
Mercedes

 

The biggest difference about a transverse spring vs a paralle leaf spring is the transverse springs are mounted with a significant amount of pre load tension before they start carrying any weight at all. That preload tension throws all most everything you think you might know or learned about leaf springs and pickup trucks right out in the bed of the truck. You can't apply that general leaf spring stuff to a transverse spring.

The current listings by suppliers do not list or give enough information to select a transverse spring from their cataluoge. They should list the eye to eye dimensions and the free arch height as well as installed eye to eye and installed arch height. From that point ,with the significant amount of pre load tension in-THEN BEGIN WITH THE SPRING RATES calculation.
When installing a transverse spring, the first thing you do is spread it, that increases the eye to eye and simultaneously reduces the arch. The preload tension on a multi leaf ,consecutively smaller makes "calculation" incredibly difficult. That's why EVERYONE has to play with leaves removing and swapping in a trial and error fashion. Even still the missing info would greatly help.

A lot of setups I see have an arch that too high, guys want lower and flattening the arch makes the spring too damn long eye to eye. One of the suppliers out there is very wrong.

 

Over the last almost 40 years in the chassis business I have build 100's of 32-34 chassis with buggy springs front and rear. I have always had my own custom width rear main built (44 inches) and used a Posie spring pack, along with Posie front springs. I have used P&J 35/40 rear spring hangers with ladder bars on all my buggy sprung cars. My feed back over the years has been that my customers like the buggy spring ride better than coil overs. I have built both for myself and currently have 4 buggy sprung deuces and one with coil overs. I also prefer the transverse spring suspension.

 

My mind works overtime,,, I think way too much. The transverse spring seems to pull up on unsprung weight.

 

A transverse spring is a great use of a single component that provides simple but effective suspension for a multitude of uses. It certainly has passed the test of time and such simplicity has been seen on drag strips and salt lakes at speeds that never could have been predicted by the original innovators of such suspension, but besides that, it also lends itself to doing real well during its time of conception by riding all kinds of terrain thru the early days of motoring on many continents around the world.
Not a bad effort for a old buggy spring...

 

I've come to the conclusion after only ever using transverse springs up front on hot rod projects, that I prefer using Teflon pad on several of the longer leaves and in the future I intend to ensure that my 2nd leaf after the main extends almost to the rolled eyes.
I am over the flattening out effort that seems to develop over time where the 2nd leaf does not seem to be long enough to fully support the main leaf how I would like.

 

My '29 Model A Woody had lean to the left that bugged the hell out me. I put a 2 degree wedge shaped shim on top of the front spring and she sits nice and level now.

 

You migh really like a factory spring then.
The main leaf has eyes, the second leaf has a safety catch
The next leafs are hollow ground with almost knife edge tapers
And they are made to take grease.

The aftermarket springs are no where near as nice in appearance or design.
The use flat profiles, Teflon slip stuff, sometimes an ugly ass button and bulges no second leaf safety.

 

Yeah, those Teflon end buttons tend to make the leaf sit not right.
Grease sure is a tried and proven method.
I definitely feel that the main leaf always needs additional support from the 2nd leaf close to the eye.
I got a buddy who cut the eyes off a main leaf and tailor fitted to his main leaf and that made a difference to how the car and spring looked.

 

Do leaf springs go bad?

 

I would like to hear more details about the preload tension, ie, how do you determine how much, and how is it done.
Krylon32, with your extensive experience, do you fit your front and rear transverse springs under preload tension, or is this not necessary ?
Thanks
Clemens.


.

 

Yes, I also believe that this point is often overlooked.
With reversed eyes, I have seen the second leaf too close to the eye of the main leaf, to the point of touching when under load.

 

Most of the cars I have seen with bad handling have bad shackle angle for starters, most of them have non parallel steering drag link to the the wishbone, some even have the spring resting on the frame that wasn't relief cut for the cross member. The steering link crossing 6" in front of the tires always leads to sketchy ride and drive. One thing to keep the death wobble out that always seems to be on the money, 45 degree shackle angle, minimum 6 deg caster, min 1/8" toe in, and make sure the thrust angle is 100% verified by cross measuring to the rear axle.

 

I assume a dead perch is using a shackle on one side only.Why do that on a street machine? On a high arch spring ( rear spring on Model A or T) when the spring is compressed the effective length is increased considerably causing a shackle angle problem. I eliminated or minimized the problem by installing adjustable load bolts in the cross member aprox 12" apart. This prevents the high arch center 12" from flexing , resulting in a more progressive spring rate. If the results give too harsh a ride remove leaf or leaves directly above main leaf. Also the ride height can be fine tuned by adjusting the load bolts. Any opinion on this? Greg White

 

Do you have any pic's of these adjustable load bolts, I am not familiar with them.

 

A critical part of installing a transverse spring is how you set it up during the early stage of a project build, whereby you are trying to achieve the stance.
How is that best done for both front and rear???

 

A pretty good trick that gets you really really close is to remove all the leaves but the main. Set it up so the crossmembers hit there. Put it all together and you'll be really close.

It's much much much easier to adjust the ride height up as much as an inch with a small shim/block but not so easy to come down.

 

Anytime you need a spreader, there's preload tension. It Should be all the time on a buggy spring set up but it's not. Anytime you need to assemble a spring pack after the shackles go to the main leaf- that's pre load tension.

 

I learned that if the pin is not welded in, it will work loose and stretch the hole out!

 

I like never seize

 

Pete Eastwood sez:
Back in the late '70's "Jake" did illustrations and explanations of all of this & it has been in every Pete & Jake's catalog ever since.

I wish everybody would get a copy & read it !!!!!

It's basic geometry, but you have to consider all the factors. (You all took geometry, right ?)
Sprint cars have the dead perch on the left side, they only go left & are pulling on the dead perch side. But they have side steering and are just trying to limit axle movement on the shackles. Not much impact on steering.

Now on to hot rods.
Cross steer with a transverse spring, should have a panhard bar or dead perch. Dead perch is the easy way out, a proper panhard bar is better.
Ideally the panhard bar should be the same length as the drag link.
The steering box & the panhard bar should both be mounted on the same side of the chassis.
The opposite end of the panhard bar will attach to the front axle/wishbone/hairpin(what ever works best).
Picture looking at the front of the chassis, head on at ground level. The panhard bar & the draglink should be parallel ( at the same angle). The goal is for the draglink & the panhard bar to work together & not fight each other. If you do these things, you will have no bump steer.
A dead perch simply turns 1/2 of the spring into a panhard bar, therefore, the dead perch should be on the right side of the car.

Go read your Pete & Jake's catalog !!!!!

PeteE

 

You know the entire set up works, it works well too, it's on millions of cars for millions of miles.

But

The entire car and the entire farm is riding on those 3/8" shackles. Drives me nuts.

We gotta have 1" fasteners, 4x 5 1/2" lugs, 5/8" shock mounts, 3/4" bolts, 5/8" bolts all sorts of stuff to mount a turn signal, backed up seat mounts and then let it ALL ride on 3/8 shackle pins. Nuts ain't it?