77 911S rear spring plate/torsion bar issues

[snow911S]

Hello Everyone,

I'm having some rear suspension issues and this is my first Porsche build so I'm hoping some more experienced Porsche lovers can help out this greenhorn.

I have purchased the sway-a-way adjustable spring plates to allow me to be able to lower the car and adjust the rear suspension more easily. I'm an Engineer by trade and have lots of experience rebuilding and modify classic cars, but this is my first Porche. I took apart the rear suspension, installed the new spring plates on the left side without issue, but when it came to doing the same thing on the right side it is as if the torsion bar is too short. The bar installs fine into the chassis but when I installed the new spring plate it only engaged 1/4 of the total spline length. When I put the bar so that it was engaging 100% of the splines on the spring plate end of the bar, the splines on the other end didn't touch at all. It is as if the bar is too short, any advice would be greatly appreciated.

Thanks in advance!

Mike.

[75 911s]

Hello Mike and welcome to the forum. I purchased a set of Sway-Away for my 75 and during the research phase I came across the very issue you are having in another thread.

Edit, this is the thread where the thread engagement was an issue, he modified the spring plates

Issues with Sway Away

And my thread here

[snow911S]

Duane,

I also had an issue with the splines and had to modify them to get them to mesh properly with the ASP's. I'm thinking it must be a different reason that causing my issue because everything meshes properly, the bar itself just isn't long enough for some reason to engage the spring plate and the chassis splines.

[wjdunham]

Oops, this reply was meant to go in another thread on the Sway Away spring plates. I'll leave it here since it's not too far off topic I guess...

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I recently installed a pair on my '85. I did not have any issues with the length or amount of spline engagement, but did need to file the splines a bit to get them into the outer cover.
I was concerned about the adjustment bolt walking off it's "perch" so I made some modifications you can see in the photos. There is not a lot of clearance for the bolt head on the inside, but enough so that the scheme worked and I don't need to worry about the two halves separating and the suspension collapsing.
If I were to do it again I would have stuck with the original Carrera spring plates as the sway-away doesn't offer that much more adjustment range. It's not like you are going to be able to radically adjust the ride height without having to re-index the bars, only fine tune things once you have the indexing close. The plates are a bit thicker if that makes any difference. They might be a better option for early cars without the adjustability that came with the later spring plate design from the factory.
Bill