Suspension Question

shaihulud Custom Title Time!

1,448 posts · joined Nov 2005 · 21 Dec 2011, 12:39 pm

#877943

I'm in the process of re-building a short wheel based buggy onto an 1958 pan.

It has a king pin front end and a swing axle rear end.

The brakes on the front will be converted to 4 stud discs. The rear is stock 4 stud drums.

It has a much reduced 1970 Beetle body so it will be heavier than a fibreglass bodied buggy and lighter than a Baja.

It has the original sway bar on the front. Because of mainly on road use I intend to keep that there.

I've removed the Z Bar or whatever it's called from the rear. It broke when I was removing it and I'm wondering if it's worth my while to fix and re-fit it.

This vehicle will be used mainly on road with only occasional fairly gentle off road use.

What does that rear Z bar do?

Why was it there?

Should I re-fit it?

Will it make much diference if I don't re-fit it?

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 21 Dec 2011, 2:28 pm

#877959

would love to see pics of the beetle buggy...

the z bar acted a bit like the front sway bar...

and stopped the rear axle from going positive camber like the early cars..

it must make a difference otherwise VW wouldn't have put it on.

the bump rubbers would be hard to find new these days as All beetles sold in North America from 1969 had IRS rear ends...
so only used on 1967-68 models...

LEE

I haven't had a front sway bar on My beetle so, I'm hoping it will make some kind of difference too...
when i get it on...
LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

hulbyw Insano Dub Head

819 posts · joined Sep 2009 · 21 Dec 2011, 5:20 pm

#877983

The Z bar does reduce wheel tuck under. Mine is shimmed so that it activates earlier. Makes a difference to the handling on a swing axle car. If you need new rubber bushes they are available as a kit from CIP1 in the USA or from Vintage Veedub in NSW. Also Wolfsburg Automotive have most of the bushes in Vic.
Lee, the front sway bar will make a good improvement.
Cheers......wayne

shaihulud Custom Title Time!

1,448 posts · joined Nov 2005 · 21 Dec 2011, 11:35 pm

#878039

O.K. I'll re-fit the Z Bar.

Thanks for your info.

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 · 22 Dec 2011, 7:12 am

#878054

Sorry to the above posters, but do your research or look under your car. The Z bar is purely an extra torsion bar or overload bar. As the vehicle rear suspension compresses, the Z bar starts to carry load and help support the load. It has nothing to do with wheel tuck and will only help reduce NEGATIVE camber as more load is carried. It was VW's way of trying to have a soft ride without compromising load carring ability.

Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

AA003 Custom Title Time!

1,189 posts · joined Oct 2011 · 22 Dec 2011, 7:36 am

#878057

matberry wrote:Sorry to the above posters, but do your research or look under your car. The Z bar is purely an extra torsion bar or overload bar. As the vehicle rear suspension compresses, the Z bar starts to carry load and help support the load. It has nothing to do with wheel tuck and will only help reduce NEGATIVE camber as more load is carried. It was VW's way of trying to have a soft ride without compromising load carring ability.

Yes it's just like a progressive spring. It probably would be usless on a lightweight buggy.

I read it on samba, so it must be correct.

Sometimes Volkswagen dealers sell spare parts. Amazing isn't it!😂

HappyDaze Superannuated

2,887 posts · joined Jun 2009 · 22 Dec 2011, 8:08 am

#878064

The 'Z bar', which has a similar effect to a 'compensating spring', will only work properly if it is connected to the axles via a rigid coupling. As Matt said, a stock VW 'Z bar' is really just a 'helper' spring. A 'Z bar [or comp. spring] does NOT work like a sway bar......in fact id does the OPPOSITE.

Racing 356 Porsches [swing-axle] mostly use very stiff comp. springs [or Z bars], with the torsion bars doing very little, other than holding the spring plates in place.

I'd rather wear a Beetle out by racing it than by polishing it!

shaihulud Custom Title Time!

1,448 posts · joined Nov 2005 · 23 Dec 2011, 2:57 am

#878173

Hmmmm!! That's very interesting. I wondered what it was for.

I seem to not need it on a lighter than stock vehicle.

Having raised the body by 2 inches on a lift kit, I'd have to modify it to be able to re-fit it, so I won't bother if I don't need it.

Thanks for your info.