I had a sports Mini in the distant past and it had short trumpets like yours. In those days, mid 70's you could buy the trumpets with or without mesh grills attached. Mine I hasten to add had no mesh grills. You're right in that the foam socks break down and quite quickly too! I removed them after one dark night coming home from Aldershott to Kent whilst in the Army and picking bits out of the one blocked carb. I ran that car with just the open trumpets for another 3 years then gave it to my brother when posted to Germany and he did the same before selling it on. Look at the old TR engined cars they had open trumpets!
Yes I think I would probably fashion a clip on mesh that covered all 4 trumpets but unless you are doing some form of off road I'd use it like that!
Doesn't half up the performance and its so nice hearing it breath too!
