Tech Week !!! Hot Rod Suspension Simplified!

[38Chevy454]

There is a reason Ford used this system for so many years. It works and has few problems. Nice write-up with a lot of details and pictures to explain. A tech winner in my opinion.

[falcongeorge]

Nice. I have a project I am just starting out on, usually I like to have every detail planned before I start,but locating the rear has been a bit of a quandry. I am planning on using an early drop-out pumpkin 10 bolt, have been scratching my head, and looking at, then tossing one idea after another. Thought about something like this, but the details were a little foggy. This is good. Dont know if I will end up with this, but I will sure really think about it.

[KWashburn]

Another excellent write up.

[Beau]

.....and watch the price of 35/36 radius rods SCYROCKET! Glad I found a pair last week!

[rat bastad]

Beautiful work dude !

Rat

[Wardog]

Love this tech week or not! Have subscribed and I will use when it comes time to set up my a model.

[deuce354]

Well Done!!!!!!

[pasadenahotrod]

Originally Posted by striper

One thing I wish I had known before I did mine was the affordability and availability of these. Would have save me cutting the ball cup out of an otherwise perfect '48 frame.

The cup you have illustrated is Model A Ford. This unit can be used with wishbone balls from 28-40 Cars and 28-41 Pickups. Replacement rubber bushings are available Ford Part number B-3446 from your favorite early Ford parts source.

The wishbone ball from 41-48 passenger cars is larger and seen in a post here with the concentric circles around the rubber and can be used if the proper cup can be cut from any 42-48 car frame crossmember. The replacement rubber bushing is available as well Ford part number 11A-3446 from you favorite early Ford parts source. They may also have the replacement steel bottom cup.

[pasadenahotrod]

Originally Posted by SamIyam

I probably need to clarify what I was saying... because when it's all said and done, I think we'll be on the same page.


I used a '40 Ford spring... and used the '40 Ford rear end that the spring came off of to get my measurements from "eye to eye" on the rear end.

When the body is off of the chassis, and all of the springs are in the spring pack, the spring is definately under tension, in fact... it's under the same tension as it was stock, because the mounting points on the rear end for the shackles, are the same.

If you use the stock measurements, especially on a light car, there is no need for a panhard bar.
I removed a couple of springs to make it right... as the stock '40 spring pack is a bit stiff for a Model A.

The real test will come when I get my first drive.



Sam

Yes, the important thing to do is duplicate the original mount dimensions for the spring you are using. This puts the spring, regardless of leaf count after "tuning" to your weight requirements, in tension as designed by Ford so as not to require a Panhard rod.

Removing leaves from the spring for weight differential won't affect the dimensions as far as fit and function go. Even a Model A spring set, with the possible of the 28-31 roadster spring, would need a leaf or 5 removed for a good ride.


The exception to this would be the 42-48 Ford dimensions which require a Panhard rod since they are designed that way. The springs can be used but the dimension used should be based on spring at rest eye to eye plus shackles plus 1"-1.5" for tensioning for use without a Panhard rod.

[nvr2lo]

Very cool!!!! Thats exactly how I want to build my first hot rod. Unsplit bones. Great tech ......

[39cent]

Originally Posted by pasadenahotrod

Yes, the important thing to do is duplicate the original mount dimensions for the spring you are using. This puts the spring, regardless of leaf count after "tuning" to your weight requirements, in tension as designed by Ford so as not to require a Panhard rod.

Removing leaves from the spring for weight differential won't affect the dimensions as far as fit and function go. Even a Model A spring set, with the possible exception of the 28-31 roadster spring, would need a leaf or 5 removed for a good ride.


The exception to this would be the 42-48 Ford dimensions which require a Panhard rod since they are designed that way. The springs can be used but the dimension used should be based on spring at rest eye to eye plus shackles plus 1"-1.5" for tensioning for use without a Panhard rod.

This is good info to know, I believe I observed this when I was putting a '56 265" chevy V8 in my Model A. I had noticed the difference of tension but didnt realize why it was done. I had a columbia OD rear end which I swapped for a stock 48 rear end becuz I didnt want the OD complexity.

[gregaustex]

Wow, great documentation that even a knucklehead like me can follow along. Have not read all the tech yet, but this is a winner to me!

[Tman]

Looks good, I will catch up with you this week.

[VOODOO ROD & CUSTOM]

VOODOO Likes. Nice job with the Frameworks.

VR&C.

[SamIyam]

Originally Posted by striper

Cool. I just knocked this one up after seeing what you did....



An alternative to '36 rear bones is to use front bones off a '48 (for example). They are pretty beefy.

Nice write up and good pics.

This is very bitchen! Exactly what I am talking about!

Take the concept... and make it your own!

Keep me posted on how it works!

Sam

[fab32]

Great tech Sam. Sometimes even us old guys tend to neglect the basics and how well they have served over the last century. After a foray into drag and oval track racing (only took up 30+years) I find it refreshing to rediscover the old ways that served me well right up to my college days. My "new" '32 chassis will incorporate just the suspension you've so well detailed here.

Frank

[BCCHOPIT]

Very nice work...
clean and simple
keep us posted when the body goes on the frame

[Jason Minahan]

re: torque arm:
The height of that rear pivot will determine your side view instant center and have a DRAMATIC effect on traction. if you have this point set correctly or made to be adjustable, you will stress those bars a lot more. By running a brace from the top of the diff down will prevent a lot of flex. (one member will be compression, one tension)

None of this is a big deal if you don't intend to have any traction (skinny bias plys), but if you do end up w/ some slicks or a nasty wheelhop situation, consider looking here.

Lots of info on setting torque arm pivot location on the web.

[SamIyam]

I made a little video to help explain the concept...

<iframe width="420" height="315" src="http://www.youtube.com/embed/okBrx2RTUAQ" frameborder="0" allowfullscreen></iframe>

Sam

[HotRodMicky]

Originally Posted by SamIyam

I made a little video to help explain the concept...

<iframe width="420" height="315" src="http://www.youtube.com/embed/okBrx2RTUAQ" frameborder="0" allowfullscreen></iframe>

Sam

Great Sam!Thanks

And steel tubes doesn`t allow as much torsion as wood sticks :-)
i bent up a 3/8 rod to a U-shape once to show a friend how bad that suspension design
is