Using a Torsion bar as a Sway bar

[dd-ardvark]

OK, what are your thoughts..., on a bagged rear end car, since the torsion bars are not in use, I thought why not just put a long sway bar inside the torsion housing and connect the trailing arms for better handling. Then it hit me, to be even cheaper and just use VW torsion bars and connect them to act as a sway bar.

An Internal Rear Sway Bar for bagged or coil sprung cars




In researching this concept on Porsche and VW, I found no information on this being banned as a race car rule benders trick, when switching to coil over shocks…, giving me the impression that no one knows of it or at least written about it.
- So for those familiar with Formula VEE racing and the way the ball joint and link pin front ends are set up on these cars, that the lower spring pack is replaced with a solid rod that connects the two front lower trailing arms together to act as a sway bar.
- Now envision the rear torsion housing of a beetle and a bar connecting one side to the other, hidden inside the housing to act as a sway bar. Again, this only works if you’re going to coil over shocks or air bagged suspension.

Assembly explanation:
- Put a Short Tube torsion plate, w/a 26-9/16” long torsion bar on one side of the car.
Push this bar through the existing torsion housings splined center section.
It will stick out a few inches offset of center into the other side of the housing.
Use a 21-3/4” long torsion bar and Long Tube torsion plate on the other side.
The connection of these two bars will be a “Sway-A-Way” #7010, 40 tooth Splined Center Section that’s NOT welded to the torsion housing.

Most people don’t need an explanation, but some do. So, a swing axle Ghia turns into a corner at speed. Instead of getting body roll and wheel tuck, it gets lower to the ground and stays flat. As the outside rear wheel is pushed up in to the fenderwell, the inside rear wheel is also picked up and this forces the front inside of the body with tire down.

In the racing world simplifying to attain the same end result and losing 4 to 5lbs. of inertia rebound weight of an external sway bar along with being able to switch bar dia. sizes and mix and match to suit your ride is king. This also makes your sway bars twist and trailing arms pivot point the same, alleviating additional suspension resistance.

David / dd-ardvark

[FJCamper]

David,

You are clever.

I know the devil is in the details, but this looks like a great idea.

FJC

[Piledriver]

A T3 front sway bar might be the right length?

Unfortunately IIRC max size was 13mm on 72-73 model squares, but it might prove to be useful.

[H2OSB]

Damn, why didn't I think of that?! If I wasn't leery of the upper rear shock mount supporting the entire weight of the car, I'd give it a go.

johnL (aka H2OSB)
www.superbeetlesonly.com

[Slow 1200]

now that's a clever idea!

I'm not so sure about your sway-bar on a swing axle theory though (roll would be the last of my concerns)

[vwo60]

Would this still have the same issues as if it was fitted with a external sway bar, the axel can still go into positive camber and take the other side with it. has it changed the roll centre.

[dd-ardvark]

Would this still have the same issues as if it was fitted with a external sway bar

Absolutely..., sizing the bar diameter to your ride and driving style is key.
As stated previously, by using the two different bar diameters as in the drawing, this was to give you the ability to mix and match to fine tune you ride. If you end up using two of the same diameter bars and it works, great!

the axel can still go into positive camber and take the other side with it.(Agreed, Yes it can) has it changed the roll centre.

NO - The roll center is still the roll center and this bar arrangement doesn't move it. That is to say..., it's effected if you move or remove weighted objects like the battery or spare tire then it will change the location. Sway bars help keep it in control. This crazy sway bar idea came about because the economy was bad and my funds were low. So their you have it, the poorer you are the more resourceful and “necessity becomes the mother of invention”.

To your Positive Camber statement: Put limit straps on the axles and that well stop your wheel extension.

David / dd-ardvark