The Jalopy Journal
Discussion in 'Tech Archive' started by SamIyam, Mar 5, 2012.
Real super clean Fab job..Great Tech very informative and helpful for future builds for my next ride. Is the frame your handy work also?
You get my vote so far!
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 frame is actually a new raised and narrowed perimeter frame from these guys:
I called them up and had them deliver it to the Turlock Swap Meet in January of 2011.
The basic frame was $700...
I should also bring up the idea of a "Torque Arm".
A good friend of mine is using this system in the rear of a roadster. He wanted a little extra insurance... and added a torque arm from the top of the rear end to the yoke.
I personally do not think it is needed... especially if you gusset all of your joints.
If you think about it... it is common practice to run wishbones, albeit split, on the front of our hot rods.
Cars stop much faster than they accelerate. So, the forces exerted on the front wishbones are greater than can be exerted on the rear 'bones.
In addition, with tires that spin... the force is even less on the rear 'bones.
I have a theory that the reason people have cracked or even broken rear wishbones is because they are split, therefore may be experiencing torsional stress... and depending on how they are anchored to the frame... results can be disasterous.
Great thread Sam. Beautiful workmanship.
My vote is for this thread. Nice work and good pics.
Great tech thread! Glad to see this method (unsplit bones rear suspension design) is gaining traction. I did the exact same thing on my '33 frame, but not nearly as nicely as yours. Great workmanship!!
Great explanation, awesome work. Thanks!
I have always been interested in building a Tradtional car. I have been doing research and just talking to people. I REALLY ENJOYED YOUR POST. Thanks for the info.... And your right most cars and sedans usually DONT have a rear seat. Just a huge hump... I like your way much better
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.
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.
Another excellent write up.
.....and watch the price of 35/36 radius rods SCYROCKET! Glad I found a pair last week!
Beautiful work dude !
Love this tech week or not! Have subscribed and I will use when it comes time to set up my a model.
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.
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.
Very cool!!!! Thats exactly how I want to build my first hot rod. Unsplit bones. Great tech ......
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.
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!
Looks good, I will catch up with you this week.
VOODOO Likes. Nice job with the Frameworks.
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!
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.
Very nice work...
clean and simple
keep us posted when the body goes on the frame
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.
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>
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
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