I had a roof rack on my Grand Prix (now it sits in the basement) and with the fairing it was fine. I had an older unit originally without a fairing and it was LOUD.
Zillon, excellent photo! Yours are always so nice.
2012 Yellow Blaze Focus SE Sedan (DD+Project)
1992 Bright White Grand Prix SE Sedan (Project)
SR #74/SMk3C #17/YBOC #03