Suspension travel check - what is normal?

[Cloggie]

Just doing rear suspension assembly (ASP, all Elephant components, 28 mm rear torsions, Bilstiens etc).

Put the whole thing together and thought I would cycle the suspension (the car is on a stand) to see if everything moved through the suspension travel smoothly and all.

Well, I was surprised that there was only about 7 cm (call it 2 1/2 inches) of total travel from full droop to full compression - no shocks or sway bars connected.

Is that it? We really only have a few inches of rear suspension travel? I thought for sure there would be at least double that...

Fronts I have not checked fully yet, but they appear to be similar travel!!

I also note a slight difference between the DS rear suspension travel (6.5 cm) and PS (7.5 cm) which seems odd.

I did a search but could not come up with a definitive "normal" travel at normal, or in may case - European, ride height.

I am shocked I tell you.

D.

[Mixed76]

What's limiting the travel? Are you hitting bolts by the torsion bars or is the swing arm hitting something. Or is the cv joint or sway bar binding. Sway bar will resist movement if only one side is moving...

My 76 has at least 4" of travel, probably >6", with everything connected.

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[Cloggie]

Originally Posted by Mixed76

What's limiting the travel? Are you hitting bolts by the torsion bars or is the swing arm hitting something. Or is the cv joint or sway bar binding. Sway bar will resist movement if only one side is moving...

My 76 has at least 4" of travel, probably >6", with everything connected.

Sent from my Pixel 7 using Tapatalk

There is absolutely nothing hitting anything, and to be fair, the car is not yet fully assembled and only the transmission and a mocked up engine (no P/c's, intake, exhaust etc) so the back is definitely lighter than when the car is completed.

I lift it until the stand the car is currently sitting on lifts off of the floor...perhaps with more weight the suspension would deflect more?????

This also has heavier than stock torsion bars (28mm) and the ER ASP...

I did think that perhaps the ER polybronze bushings were binding, so took that apart and put in an extra shim, did not make much difference.

I find it most interesting that both sides have similar travel (~3 inches) and certainly the search I did on this forum, while definitely inconclusive, seemed to suggest travels closer to 3 inches than the 6" you have on your car.

Still wondering, but can't see anything wrong and to be truthful, this is a pretty simple mechanical system, nothing fancy or hidden to jam up or block...at least not to me...

Thanks again,

D

[Mixed76]

If the torsion bar is installed you're measuring full droop to the torsion bar taking up 1/4 of the cars current weight. I.e., not even normal ride height.

Take out the torsion bar and you'll get the full travel.

Sent from my Pixel 7 using Tapatalk

[Cloggie]

Originally Posted by Mixed76

If the torsion bar is installed you're measuring full droop to the torsion bar taking up 1/4 of the cars current weight. I.e., not even normal ride height.

Take out the torsion bar and you'll get the full travel.

Sent from my Pixel 7 using Tapatalk

Ok, that gives me some comfort and makes sense -and is the correct way to look at it as you are completely right, all I am doing at this point is taking up vehicle weight, no jounce travel as I am not jouncing it at all.

I actually did as you suggest and everything was smooth right up to the point where the ASP began hitting chassis elements so that is good I guess....

I guess in some perverse way I just need to get on with finishing the blessed car, get the engine done and then just take it for a drive.

Considering this was a full down to the metal rebuild, I sure there will be other issues that will require me taking stuff apart again.

At least it is all new fasteners, properly antisiezed and ought to be not too much hassle....plus I have a lift.

But still curious what the normal travel is supposed to be.....I still am a little shocked by all this, but perhaps in my twilight years I am getting more delicate....

D.