Buggy Suspension

[JCS]

I just bought a VW dune buggy with shortened IRS chassis. It has not had any changed made to the suspension stiffness and rides rough. It has been many years since I have built or fooled with a buggy. What is the best way to soften up the ride?

I was thinking about removing one of the front torsion bars or installing a lowering kit and adding caster shims. I do want the front and rear a bit lower.

On the rear, I was thinking about moving the torsion bar one or two notches to soften up the rear. Now, the half shafts angle downward towards the wheels a bit and I think it would help with a slight angle upward to wheels ......for lowering and ride.

[oprn]

The first thing I would look at is tire pressure and size. Chances are pretty good that the last tire shop jacked the pressures up to maximum. Wider tires at lower pressures will go a long way to taking the harshness out of the ride as will taller sidewalls.

Lowering the ride height alone will do nothing to improve the ride. In fact if you go low enough you will need to stiffen it up to prevent dragging bottom.

[Dale M.]

[JCS]

With little weight on the front suspension, the trailing arms are angled down so much that the new vw shocks are almost out of the sleeve....therefore not having much travel. If I push down on the front of the car it is difficult to get it to go down an inch. Since there is no appreciable trailing arm travel over bumps, all the energy is transferred to the front of the car, making it want to bounce the front wheels light (unsafe). Using the adjusters in the front may be my best option with the lowering involved as well. I did a dune buggy back in the early 1970's and there I took out one set of torsion leaves. I just do not remember what I put in it's place. That was in the day before adjusters came along.

The rear has more travel because of the engine weight. I think maybe one notch will do unless someone has more experience on dune buggies and would suggest more. I think one notch would make the half shafts level or even angle up just a bit, lowering the car and giving a little more torsion travel.

I will check the tire pressure but this will not correct the severe trailing arm downward angle in the front.

[didget69]

[JCS]

I "just bought this buggy" 2 days ago so I did not install anything.

It has new shocks on it. I am not in need of any other shocks as I do not plan on jumping or off roading this car.......just a street buggy and then sell it down the road...maybe in a year.

I did look in my storage building and examined an old Formula V chassis I had there. The front end had a torsion rod that fits in place of the torsion leaves on the lower tube. I am going to replace the leaves in the lower tube with this torsion rod. It was used in FV to soften the suspension and to act as a stabilizer. (A round spring steel rod with about 2 inches on square metal forged on each end with countersunk area for the trailing arms Allen screws to set in place. I do not know if these are even available any longer for FV.)

At 71 I am just playing with cars in between fishing and hunting. I have had many vw cars over the years and still enjoy fooling around with them. Just finished a complete restoration of a 71 standard bug and will be starting a road/track car using Miata running gear this fall/winter.

[Tom_Kathleen]

This place has the F/VEE front sway bar in a few different sizes. http://www.sracing.com/Store/FV_Stuff/FV_Stuff.htm Look under the front suspension area. Tom
_________________
Manxter #16, 1968 Meyers Manx & Kick-Out SS #16 (WIP)
Manx Club & CVA

[didget69]

[oprn]

[Tom_Kathleen]

Maybe, but the only F/Vee swaybars I have seen are internal to the beam replacing a set of the tosion leaves. I raced F/Vee many years ago in another lifetime. LOL Tom
_________________
Manxter #16, 1968 Meyers Manx & Kick-Out SS #16 (WIP)
Manx Club & CVA

[JCS]

WOW...........I replaced the lower torsion leaf strips with the Formula V rod today and took the car out for a ride. WOW I say WOW what a difference. The ride height is a little lower so that the trailing arms are almost parallel with the road. Yesterday I had lowered the tire pressure to 15 on the fronts and 20 on the rear since they are wider tires. That helped "some" but softening the front torsion suspension really did the trick. Now when I hit a bump the suspension takes the energy and then the shock dampens out that energy.
The car tracks so I can run 50 mph with no hands. I took it on an especially bumpy blacktop road and there were no more noises caused by the car taking all the energy from the bumps or the tires bouncing like a basketball. After I lowered the tire pressure yesterday I took it on the same bumpy road and there were several rattles and bangs due to the energy transferred to the car from the road and no suspension and shocks helping to dampen it all.
I highly recommend you try this on your buggy, especially if your trailing arms are not near parallel with the road. The bar I used may be the same as is listed on the this suspension thread. If you have a light weight buggy and your trailing arms are not parallel to the road, find one of these bars. I put mine in the lower tube today. That was the same as in the Formula V.

Just a note; a car does not have to have great power to raise the wheels off the ground and cause bounce. All your car has to do is have stiff suspension and hit a bump. The wheels will come off the ground, even if only a bit. So you have your hands on the wheel and they turn the wheel slightly. When the wheels make good contact with the pavement, the car will go the direction the wheels were turned, the driver sometimes corrects and sometime will over correct, the car gets squirrely and the car goes out of control, sometimes in ditch, off the road, sometimes upside down.

I will put some photos on the this thread if I can figure how to do it. I am not real tech minded with gadgets. I took photos of the bar and the ride height.

[cbeck]

The torsion bar eliminator described sounds just like the thru rod off road guys use when converting to coil overs.

[prkid424]

[hillmotorsports]

The replacement that the formula vee guys use is an anti roll bar, not just a through rod. They make them in 1/2", 9/16", and 5/8".
The formula vee manufacturer that I spent time with expressed concern as to the suitability in a buggy. Against his advice a customer installed one in a Manx clone, it broke THE REMAINIMG TORSION LEAVES... he claimed it was due to the weight.
He DID think it should work on a Tow'd as their front axle weight is considerably less with the fuel tank mounted behind the driver/passenger.
I was surprised he was aware of the Tow'd it he said he has been around all things VW all his life.... he's in his late 60s now.

I EDITTED THIS POST THIS MORNING WHEN I NOTICED A MISSING PART OF A SENTANCE. PREDICTIVE TEXT PERHAPS?

Paul
_________________
Rosemarie and Paul Hill
Morrisburg, Ontario

(With way more projects than spare time!)

[JCS]

Paul; I can fully understand how a buggy could brake one set of torsion bars, especially if it is run on rugged ground and jumped. I would probably not use the through rod and only one torsion bar if I ran it that way. I will let you know if I have troubles.

The buggy will just be used for occasional street use.

Good discussion guys.

[vponder]

Does anybody know if that shop in the shared link is still in business ? I clicked on it to see what the price of the FV bars were. Got a stock rebuilt beam that is stiff on my Sportster, running cheap oil shocks, and low air in tires still stiff.

[Dale M.]

[slalombuggy]

I've been running a 3/4" FV style swaybar in the front of my buggy for 8 years and have not had a problem with the front end at all. Unlike the FV guys I did not use round rod with square tube welded on the ends. I used a solid 3/4' piece of bar stock. I just had to sand the ends of the bar slightly to fit it in the trailing arms.

brad

[vponder]

SO how much sanding is involved or is it more grinding to fit. and just the stock grub screw holds it in place? Also did you put it in the top or the bottom tube ? Thanks

[slalombuggy]

There isn't a lot of material to take off, a heavy sanding/light grinding to make it fit.

I put it in the top tube of my street buggy so I can reach the adjuster with the hood on.. My LSR buggy is getting one in the bottom tube just to keep the adjuster out of the salt.

Some people have also run 2 adjusters and set one lower than the other. That way the springs act in a progressive rate. One set of springs bears most of the weight, but as the suspension compresses it gets stiffer as the second spring starts to load more and more. If you offroad your car much this might be a better alternative. But for a street car a solid bar will work best.

brad