What's this 411 S5 part?

[Kevin H]

See attached pic. I know what this is, but it's pretty obscure and not a part that most owners would ever see or even be aware of. So I thought it would be fun to see if anyone knows what it is. Sorry, no prizes other than cognoscenti kudos :-)

[guymd]

I don't recognise it, but suspect that it's a flexible flap on an air passage, and that the pink things are backing where the material is tied through to something. Is it a soft lining for an air damper on the heating system?
If I'm wrong, this contest is rigged.

[Kevin H]

guymd, you're getting warm but it's not part of the heater system.

I've attached a picture of the other side - the pink things are rusty rivets that fix two metal plates (one slightly larger than the other) which sandwich some sort of rubberised fabric material which is now perished.

[Thor]

I am a bit annoyed about this because I feel sure I have seen these on a partially dismantled Bristol before. It's a guess, but are they flaps which allow air to pass through the fan cowling when the fans are not running but close up and seal the cowling to force more air through the radiator when the fans are running ?

[Kevin H]

Originally Posted by Thor

It's a guess, but are they flaps which allow air to pass through the fan cowling when the fans are not running but close up and seal the cowling to force more air through the radiator when the fans are running ?

No, sorry, that's not it. Does such a thing even exist?

I believe the part is common to all 411 series, but I think (not 100% sure) that it is unique to the 411.

[Thor]

Yes, such things do exist on some cars, and Bristol being brilliant aerodynamic experts (!) might well have added such a brilliant feature !!!