Turning lid upside down does nothing other than make more induction noise. More air can get into the can but more air can get out also. A snorkel or hose to a cold air source works much better.
I've had the snorkel and hose + metal pipe idea for a blue 202 "been looking at the desgins from other cars" but this would require to cut a certain amount off the air cleaner nose and move the battery into the boot...
I've got another idea it starts on the left hand side of where the grill should be, next to the radiator.. The motor fan would have to be removed and replaced with thermo's as the hose could get caught up then cut up!
how about if you turned the aircleaner upside down and put a small scoop above it through the bonnet?
you could block off the original snorkel.
there would be plently of cool air coming in.