Spring platform rubber rings

[rossocorsa]

Just bought poly versions off Mark but these come smooth rather than with the ribbed surfaces (which sit facing the platform, the smooth side sits against the spring ends) just curious does anyone know what the function of the ribs is and what difference does their omission make?

[HFStuart]

I think the ribs are there to provide a gap into which moisture and crud can seep helping the rust get a good firm hold....

More seriously they'd give the rubber seat a bit more give so I suspect they were designed to reduce ride harshness

[peteracs]

Maybe there to allow the spring to move more easily relative to the rubber and the support as it goes up and down?

Peter

[rossocorsa]

Other theories to provide more grip to stop the ring moving or to allow drainage. I am wondering if it is intended to allow the rubber cushion to flex as the spring moves slightly due to compression/expansion? Lancia design fascinates me when you look at details it shows how lancia engineers, despite Fiat and maybe even Citroen parts the Beta was still designed by Lancia, thought carefully about everything they did the sad thing is how so much of the how and whys is lost in the passage of time.