Treating excessive roll - SCCA RallyCross Beetle

[FJCamper]

Hi TouringBubble,

I wish there was something we could do to help out with handling, but dirt cars and asphalt cars are so different -- and we know so little about dirt.

Good luck,

FJC

[TouringBubble]

I know it Frank! I'm a little off the radar with my use of the car, so I'm learning as I go.

Speaking with Sway-a-Way this morning, they suggested the 27mm short bar and the front leaf upgrade. I felt like that was a little stiff, and was a little concerned with going to the 21" bar because I don't want to get near the limits of it's travel. Based on that, and the specs from Mark, I've settled on the 24" 26mm bar and front leaves. I'm kinda splitting the difference. I'm going to see how that feels and then consider sway bars and maybe ballast from there.

[Steve Arndt]

The length of the bar doesn't change the potential travel on a standard setup.

With long offroad arms and extreme travel the longer bars are needed to not over twist the bars and fatigue them. That is coil over territory, 12" plus travel. Your stock rear suspension has ~5".

So you can use 21", odd ball middle length 24, or 26" length torsion bars, your choice. The diameter (size in mm) you choose is based on the length and desired spring rate. At the same diameter, longer length equals lower spring rate.

There is a force/degree of twist chart on SAW's website.

To iterate, the length you choose doesn't determine the travel.

[Steve Arndt]

Here it is.

http://www.swayaway.com/TechRoom_VWguides.php

[Piledriver]

It's not a matter of preference...
...the only bar that fits IRS is the long bar unless you have modified swing axle spring plates or something.
Softer=more bite, generally speaking, but also less roll resistance.

[Steve Arndt]

You can run short swing axle 21" length bars on IRS, BUT you need the aftermarket spring plates to do it, and solid/short bushing covers.

Go for the 26" (stock late IRS length) bars. Select a diameter that gives you the desired spring rate. I would recommend 25 to 26mm diameter.

I run 23.5mm longs on my high power baja and it works great for dual sport. IF I was setting it up to rally i would go up to 26mm.

[TouringBubble]

Okay ... that's good info. Thanks a ton!

I have the 944 spring plates. Is that still correct for the long bar? I'll likely do the 26mm long bar then. I liked the rate of the 24" bar better, but the longer one is still close.

If I can do the 21" bar, I'd rather do that, but I don't know if I can do that with the 944 spring plates and an aftermarket cover. The 25mm 21" bar is about the same rate as the 26mm mid length bar.

[Steve Arndt]

944 only came with 26 inch length ("long") bars.

[TouringBubble]

26mm long bars it is. Thanks for saving me from a mistake guys!

[Fiatdude]

oh,,,, there are plenty of mistakes still to be made LOL

[TouringBubble]

oh,,,, there are plenty of mistakes still to be made LOL

Absolutely!

[TouringBubble]

So, here is what I went with ...

26mm long bars for the rear
944 spring plates
stiffer front leaves
front adjusters
"lowered" camber bushings
boxing in rear control arms (or whatever they are called on VWs)
fabricating a front "tower" brace

Already have KYB Gas adjust shocks, fixed "kafer" bar to triangulate the rear. We'll see how it works out. Next event is Apr 27.