Author Topic: Z-Bar on Rear Axle?  (Read 1746 times)

Jack the Knife

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Z-Bar on Rear Axle?
« on: February 03, 2023, 22:57:47 »
A friend who used to race Porsche 356s mentioned to me that the late 356 used something called a "Z bar" to help tame the last of their swing axle cars. I understand this innovation was passed on to Volkswagen where it remained in use on their Beetles for many decades to come. The Z-bar was used in conjunction with a leaf spring mounted transversely under the pumpkin of the rear axle, similar to Mercedes' coil spring on top of the axle with which we are familiar. 

Here's an analysis of the components of a Beetle's Z-bar, which I have no doubt is similar to that of the stock 356: https://1967beetle.com/z-bar/

Z-bars worked as a sort of camber compensator and quasi-droop limiter. That is, if the car is lifted up at the back, it prevents positive camber from developing.

Here's an extensive discussion of the Z-bar: https://shoptalkforums.com/viewtopic.php?t=122651

Has anyone else ever worked with these or put them on a swing axle car? I find it hard to believe that no one has tried this on a pagoda or even a 190.
1964 230SL
2015 G550 """Professional"""

Benz Dr.

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Re: Z-Bar on Rear Axle?
« Reply #1 on: February 04, 2023, 02:11:36 »
Sounds like something similar to what was used on a Corvair.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
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Jack the Knife

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Re: Z-Bar on Rear Axle?
« Reply #2 on: February 04, 2023, 03:10:41 »
Sounds like something similar to what was used on a Corvair.

Indeed, a leaf spring was used on the Corvair like the 356 and Beetle! But it seems a z-bar was not. Nonetheless, people have talked about it..

https://corvaircenter.com/phorum/read.php?1,880951

There's a nice photo of one there on that Formula Vee car.
1964 230SL
2015 G550 """Professional"""