The location of the horns is not ideal.
I had the experience of hitting deep standing water in a railway underpass at about 50 kph. It was like driving under a waterfall with all the water spraying up over the car. I was most impressed that no water came into the car (hood up because of the storm). What I did discover, after a few kilometres, was that my brand new pair of FIAMM horns emitted only a water sodden gurgle. They never fully recovered and I returned to the original single horn plus a matching second horn from the same manufacturer. .
I have fitted them in such a way that they don't act as water scoops
