"Dude" writes:

There are after market tubes that work better. I don't know the name, but I
rented a plane with them, and it was more quiet, and cooler.

Hopefully someone will have the name.

Your choice of Ventubes ($70 or so for the pair) or the ultrabichin'
ones from Sporty's at nearly $400 for the pair.

Both are STC'd for Skyhawks.

-jav