Swaybars

[RussellK]

At the VW Funfest this weekend I had a discussion with another Bay owner about handling on the interstate. He had an Addco Rear swaybar on his '78 and said he wasn't buffeted by wind or trucks at all. I feel the effects of wind and trucks on the interstate and while it's not terrible an improvement wouldn't hurt. There seem to be a wide variety of opinions on TS and Ratwell has a good write-up. It seems that just adding a heavy duty rear swaybar might improve one thing to the detriment of another so alternatively I'm considering installing a heavy duty front swaybar . Its about $250 shipped. Has anyone done this upgrade that would be able to share their results. In other words will I have a gee whiz this is great experience or will I wish I had my $250 back

[vdubyah73]

if you are a good seat of the pants driver, instinctively know what the car is doing, like playing in the snow and dirt and getting a little sideways makes you grin, you will like a rear sway bar. if you do any trail riding to get to campy spots a rear sway bar is probably not a good idea.

a sway bar inhibits the independence of the suspension. if one wheel is up a hump and the other side down ditch, the ditch side won't drop as far as it used to. your tire is spinning and you can't go no mo.

[Lanval]

Sway bars will usually make you stick to road better, at the expense of ride. I put beefy ones on my Volvo 240 and it was a lot more rigid. Great in turns, not so much on choppy roads. I didn't take it off road.

I doubt you'll be sorry, if a more certain ride is your goal.

ML

[vwlover77]

VW designed the suspension of the Bus for predictable handling and response, good feedback to the driver when approaching the limits of adhesion, and to skid rather than roll over. I'm content to trust their design.

Good shocks and the appropriate tires will do a fine job of reducing buffetting to an acceptable level. Sway bars cannot change the aerodynamics!

[Amskeptic]

VW designed the suspension of the Bus for predictable handling and response, good feedback to the driver when approaching the limits of adhesion, and to skid rather than roll over. I'm content to trust their design.

Good shocks and the appropriate tires will do a fine job of reducing buffetting to an acceptable level. Sway bars cannot change the aerodynamics!

Thank-you, vwlover77. While people may share subjective opinions about the crisper feel of larger anti-roll bars, they may not know that they are increasing unpredictability in an emergency evasive maneuver.

I wrote Ratwell about the potential problems with rear anti-roll bars back in 2005 at the height of our entertaining exchanges on theSamba, and he did rewrite a bit to properly document the *worse handling*.

So campers, why did VW use "Z" bars on the rear of late swing axle beetles and Type 3s.
What "Z" bars do is to turn an up on one side of the car into a down on the other!
Discuss . . .

[Lanval]

VW designed the suspension of the Bus for predictable handling and response, good feedback to the driver when approaching the limits of adhesion, and to skid rather than roll over. I'm content to trust their design.

Good shocks and the appropriate tires will do a fine job of reducing buffetting to an acceptable level. Sway bars cannot change the aerodynamics!

Those are valid points, within limits. The VW like most cars, is designed for good functionality and safety in the widest variety of circumstances/drivers. That doesn't mean the performance is optimized; rather, the original design is the one that works in the broadest set of variables. Changing design variables can make vehicles unstable, but it's more likely that it simply changes the normative characteristics. VW is OK with that; they understand that circumstances dictate methods, which is why they put some of that stuff in the manual. For instance, new VW owners ask about the best oil (meaning weight) to use; this question has already failed insomuch as it has built into it a flaw in thinking. To wit: there is no "best oil" weight, only "best oil" for a given application.

The same must be said here; changing the sway bars only changes the application. Case in point: the Volvo 240 came standard with a set of 21mm sway bars front and rear. However, when they began manufacturing the 240 GT/Turbo came with a larger set of sway bars 23mm front/rear, and later (I believe; I could be wrong) 25/23mm front/rear.

Neither of the sets is meaningfully optimal; rather, Volvo felt that someone buying a GT/Turbo would likely be driving in a different style, and consequently chose some to enhance some driving characteristics at the expense of others.

My recommendation to the OP stands; in changing the sway bars, he is changing driving characteristics which means adjusting his driving to those characteristics. His ride will be firmer, but less forgiving should he enter a corner too hot.

*************************

There is another point that I think might be made here, though I suppose Colin might want to move it, since it's really off topic here; the issue is OEM design and its relative inviolability. Having worked for several manufacturers, and knowing people who have worked at others, it is not really appropriate to refer to any product design as the "best" solution. Products are always subject to the revisions of a variety of groups ~ engineers, accountants, salesmen and even top guys who want to stamp their ego on the car.

The choice of automotive design in any vehicle is always a set of decisions based on engineering, safety, mfg costs, saleability and other, often incomprehensibly abstract influences. The stock vehicle, especially one with a long design shadow (like the VW bus) is pretty well designed; that doesn't mean it is optimized, however. As with my decision about the 16" wheel/tire combo, I would argue that the 14" is NOT the preferred solution; it's the best solution that VW thought they could offer while maintaining their cost-to-market ratio, was readily available (at the time, not so much anymore in the US) and met the safety needs of design.

The list of automotive design failures (from engineering to aesthetic) among the different manufacturers is lengthy; VW was not immune to those possibilities (nor are they now, if the Routan is any measure of what they're willing to do to make a buck) and it would most useful if we, as a community, maintained an open mind and flexible approach to how we deal with these marvels of engineering. And they are marvels; how many other models remain on the road in numbers as large as the vintage VWs? None, to my knowledge. But their excellence does not preclude the recognition that the designs are imperfect, and that there is room to improve upon them, based on experience, knowledge and thoughtful application of those elements.

Michael L

[SlowLane]

Russell, you need to be careful about adding roll stiffness to the back axle without also increasing it at the front. In general, adding roll stiffness at the rear will increase the tendency of your car to oversteer, while adding it at the front will increase understeer. An oversteering vehicle spins out more easily, which may not be what you want when barrelling along a highway and being hit by the bow wave of a semi rocketing past you.

These things tend to be highly subjective. It's a shame you and the fellow you were talking to didn't take each other's busses out for comparison runs.

Frankly, I think your money would be better spent making sure your existing steering and suspension components are in as good a shape as you can manage. Anti-sway bars aren't a panacea for a worn suspension. If you already have a solid suspension and play-free steering, then indulge yourself, but increase the roll stiffness at both ends.

[SlowLane]

So campers, why did VW use "Z" bars on the rear of late swing axle beetles and Type 3s.
What "Z" bars do is to turn an up on one side of the car into a down on the other!

Z-bars reduced oversteer by increasing the roll at the rear. They were, in fact, a true "roll-bar", as opposed to the more common "anti-roll bar". Safe At Any Speed.

[Lanval]

Frankly, I think your money would be better spent making sure your existing steering and suspension components are in as good a shape as you can manage. Anti-sway bars aren't a panacea for a worn suspension. If you already have a solid suspension and play-free steering, then indulge yourself, but increase the roll stiffness at both ends.

A crucial point that I overlooked; yes, Slowlane, you are absolutely 100% correct. A properly working suspension (bushings are firm and elastic, shocks have good pressure, wheels are aligned, etc.) will do far, far more than adding the roll bars.

Without that other stuff, adding the roll bars will quite possibly enhance the unpleasantness of the ride in that adding them reduces the ability of the whole suspension to react, magnifying areas where the suspension is worn or out of kilter.

I would absolutely recommend you make sure shocks, springs, bushings and alignment are all at OEM standard before you spend money on swaybars. Nice catch Slowlane!

Best,

ML

[drober23]

People mentioned this, but no one shared the link. ratwell.com has an excellent discussion on front and rear sway bars.

http://www.ratwell.com/technical/SwayBars.html

Worth a read if you are even considering adding one.

[RussellK]

Thank you all for your replies. I've optimized my steering with new ball joints, tie rods, centerpin, Hankooks, Boge shocks, sway bar bushings and alignment. What my conversation with the other fellow prompted my thinking was it could be even better. After research though, I determined maybe just upgrading the front would be a nice compromise given the swaybar is 35 years old. Is it possible that after 175000+ miles of twisting there is a bit of fatigue in the metal? Perhaps I should just replace the front with a stock as opposed to a heavy duty? I appreciate your varying opinions.

[Lanval]

The wikipedia site is also a good intro primer:

http://en.wikipedia.org/wiki/Sway_bar

ML

[Amskeptic]

So campers, why did VW use "Z" bars on the rear of late swing axle beetles and Type 3s.
What "Z" bars do is to turn an up on one side of the car into a down on the other!

Z-bars reduced oversteer by increasing the roll at the rear. They were, in fact, a true "roll-bar", as opposed to the more common "anti-roll bar". Safe At Any Speed.

Dingdingdingding We Have A Winner!

Anyways, VW *had* to stick those z bars on to prevent jacking where the outside wheel suddenly goes to full rebound under cornering force and flips that sucker.
Colin

[RussellK]

Has anyone seen stock swaybars for sale? All I see are Whiteline and Addco Heavy Duty.

[Amskeptic]

Has anyone seen stock swaybars for sale? All I see are Whiteline and Addco Heavy Duty.

If you go up a few millimeters on a front stabilizer bar, it is to your advantage. If you find a used one, you can readily sand it smooth and paint it. Like any spring device, pits and nicks weaken it. Your stock stabilizer bar, if in good condition, is functional until it snaps with a bang. They do not develop "sets" or weaken like torsion bars that operate in one direction only.

I have driven several more refreshed VWs recently, and in every case bar none, the steering feel and directionality has worsened significantly with new components. I am currently driving the BobD, and it feels as lovely as any new VW ever did. The key, the key, the key, to VW making this ridiculously levered and multi-linked steering work was to have very little friction so the caster/return-to-center action could "automate" fully half of your corrections. With the front end off the ground, you can rotate the wheel from full lock to full lock with one hand. Try that with your refreshed suspension. The one I checked last week in North Carolina, Tooster's beautiful Westy, required major two handed grunt. We disassembled the entire steering, tie rods, damper drag link, and found that the new ball joints were the worst offender in the friction department, followed by stiff new drag link, followed by the tie rods, and rounding up the disaster of vague wander was an over-adjusted steering box.
Colin