History DeDion axles on hot rods

My idea for a cool, light, little sports rod is still pretty much along the lines of a two seat speedster (or small sport coupe). While I'd like the rear and engine to be the Alfa gear, I'm wondering if there is an interesting alternative to the early Ford front suspension to match what is going on at the back of the car? Perhaps a straight tube deal from oval racers? Some sort of early independent system? Frame under axle with leafs? The end goal? How about entering it in Coker's big vintage race event, or something like that? Just wondering. Gary

 

I can't make out a lot of detail in the photos. Tell us more!

 

Re Torque: Yes the Rover P6 3500s uses this rear, it handles a small V8 well.

 

The basics of a DE Dion Tube axle are . The axle is a solid tube or beam to the rear of the wheel/hub center line with the hubs forward of and attached to the ends of the tube. The axle tube can be attached to the frame by any normal fitments, trailing arms, struts or in our case a set of quarter eliptic springs acting as the lower /trailing arms and a pair of adjustable upper links. The diff is mounted solid on the chassis and drives the hubs via CV half shafts. I have not posted photos of the completed unit..well because we have not finished it. We still have to design, build and install the panhard bar , shock mounts and have the axles built. The axles are being built by Drive Shaft Service on the east coast.
The good part of the De Dion is the weight of the diff is mounted on the frame where it becomes part of the sprung weight of the car rather than the unsprung weight of a standard live axle. The other good part is the camber is fixed just like a live axle.
In this case the quarter eliptic springs are nice soft units because they and the shocks do not have to handle the extra mass of a live axle.
Hope this helps.
The students will be removing the cab next week. The mechanical group will start plumbing and finishing the chassis while the paint and body group continue to work on the body. At that time I will post more photos of the chassis.

 

Here is a photo of a De Dion type axle from the rear...minus the axles, shocks and panhard bar

 

I think where I'm having trouble is seeing where the axle sits in relation to the wheels' axis, i.e. what makes up the 6-8" between that and the front face of the axle tube. It there a backward sweep to the drive shafts? Do you have a shot from the side?

 

Here is a photo of the rear suspension early in the design phase

 

I'm surprised no one has mentioned the Allard. English made, flathead Ford powered, with DeDion rear suspension (optional) and flailing arm front suspension made from a Ford axle sawn in half.

Call it a sports car but it had a lot in common with contemporary hot rods.

http://www.allardregister.org/k2-touring/

 

go to my profile and look you will find a photo of the setup in early design

 

Love the Allards... Hate that front suspension. Gary

 

x2!

 

I see. (Don't know how I missed it the first time; the square tube/round tube thing probably threw me off.)

I assume you subsequently went to the square tube with gussets to deal with toe changes under lateral acceleration? or was the round tube always just to locate things temporarily?

What size/wall thickness did you use in the end?

 

Very intresting, ive seen this set up before but never realized how it worked or how it was called.

Metalshapes, your parkin lot racer was awesome to say the least.
What Compomotive rims did it run? Those that look like a xbreed between the Minilites and the Japanese Watanabes are my faves and i wish i can score a set one day. Sorry for the O/T.

 

Actually the round tube is still there and welded in. We just added the flat stuff to add strenght. the springs are from an Austin Healey Sprite. The rest was built by the students. The final welds followed getting everthing pointed in the right direction.
I have a friend, Bobby Knighton, that used quarter eliptic springs way back in the late 50's and early 60's on a yellow 32 Altered coupe that kicked serious butt and was national champ for many years.
Mostly everything is 3/16'. There is some that is 16 gauge where strength was not a real concern.

 

Here's the latest design for the '31 project:

 

This model A was built by a friend, Christian Mühlbauer. He is from Munich and I´ve never seen a thing he built that didn´t leave me speechless. He has the Alfa transaxle / DeDion rearend in it. Everything on this car was fabricated and built by himself, down to stitching his own interior and paintwork. I wish I had half of his talent.

Here are some pics.

 

Thanks.

It was based on the tub of a Lola T 492.

This is what I started with.



I made my own rear suspension and back off the chassis, but I used the stock Lola front suspension
I also shortened it a lot from the Lola specs, made it lighter ( I missed my goal of 300Kg by only 15 Kg or so, fueled up and ready to go) with a Fiat Abarth engine mated to a Ford Fiesta gearbox, and I turned it into a center steer single seater.





The wheels were acctually Dutch made Graku 3pc wheels.
( I sometimes say Compomotive because they are almost identical, and even use the same rim halves )
Rare then ( 20 or so years ago ) probably even harder to find now.
They were Fiat boltpattern, which I wanted so I could put them on my Fiat Abarth as well if I wanted to.
( with diffrerent outer rim halves )

That has finally happened...
http://www.dogfightmag.com/forum/showthread.php?494-1000tc/page2

( and some people claim its bad to be a hoarder...)


The Blue Racer itself is long gone...

The engine is back in my Fiat Abarth.
And the tub went to a buddy of mine, who restored it back into a Lola Sports 2000.

But t was fun while it lasted, and it won me a championship...

 

Jeez, I just had a near simultaneous errection / heart attack. LOVE that rear clip! The rest is nice, too, of course. Can we get more build photos? Link? Gary

 

Of course. Here´s the whole story, I hope you can see the pics without loggin in.

http://www.oldtimer-in-teufels-hand.de/viewtopic.php?f=12&t=405&start=0

That´s what he startet with

 

I worked on a race team that ran Alfas and another that ran Lola S2000s. I know the alfa rear suspension well. The biggest problem we found that the clutch assembly was the weak link and would break shatter in the driveshaft input bearing area.
In regard to the streetrod, the students and I discussed various ideas. The De Dion set up seemed to be a very simple unit to build. This was a real challenge for the kids.
While the front axle is a standard 3" dropped axle the steering is a steering rack from an Austin Healey sprite. It is attached directly to the axle and has no bump steer or cross steer concerns.

 

Juan Manuel Fangio his cars - I would like more on that!
DeDion Axles in some form has been under a lot of rods

 

I put rear transaxle and front (Torsion bar ) suspention AND twincam engine from a Alpha GT under a Topolino. All worked very well, you could chuck it about like a Go Kart untill it rained !

 

Neat. I've been meaning to ask, but how hard is it to modifiy or fabricate a new drive shaft for these Alfa transaxles / engines? Gary

 

Doesnt look that hard to me.

Its a regular steel driveshaft that sits beween a flywheel/ringgear that is mounted on the back of the engine, and the rear mounted clutch ( on the front of the transaxle ), rubber mounted on each end with another rubber about halfway where the support bearing is.

As long as you keep everything nicely in line, I think you can chop pieces out of the length.
And probably even eliminate the middle rubber and support bearing.

 

Great news. I was afraid it was some sort of Pontiac Tempest rubber band deal or something equally goofy.

The next question would be wheels then. I wonder what kind of "vintage or traditional" wheel would fit the Alfa rear hubs, and or what to use to match US stuff up front. I'd guess wheel adapters in the rear? Gary

 

Rear hubs come in 4X98mm ( same as Fiat ), and later ones had a 5 bolt pattern ( possibly also 98mm )

Looks like there is enough meat in the flange to redrill it to something more common.

Front hubs on a Alfetta have the same 4X98 ( or 5 bolt for the later ones ) but I think the hub/disc assembly from a earlyer alfa might fit.
And that would get you the same 4 bolt boltpattern that is used on Fox bodied Fords.
( and Pinto, etc )

 

So I guess, front suspension wise, you have a lot of options...

You could stay with the 4X98 boltpattern and use Alfa or Fiat suspension parts or use just the uprights to make your own IFS.
Or you could go with the link pin IFS from a 850 Spider ( same BP, small discs and very light ) or use part of that to make your own I beam or tube axle.

Or use more common Hot Rod parts for a Ibeam or Tube axle front.

Or cut a Ibeam for a swing axle front.
That is the one I would probably do.
Despite the bad name they have, they can work extremely well ( if you get the lengths of the axles. the pivot points, and the springrates right )
And they are a proven & trad combination with a DeDion...

 

Very cool.

Thank you for posting those pics.

 

That bearing at the front of the clutch housing is indeed fragile: a good reason to retain the driveshaft centre support bearing. If things are indeed lined up properly I'd even recommend moving it quite close to the gearbox.

I seem to remember measuring an Alfetta driveshaft, for a reason long forgotten, at 70mmØ. The transaxle has three weaknesses:

1. The above bearing - it's actually the clutch front cover casting that breaks.
2. The synchro on second doesn't last long, so the 1-2 shift is often slow in real life.
3. The final drive pinion strips when subjected to really severe torque.

Edit: it wasn't the driveshaft I measured but the axle tube, and the reason was to get a feel for what size a fabricated DeDion axle ought to be. That resulted in the first prototype axle for the Morris Minor. Unfortunately the thinking has moved on a bit since then ...