When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Just switched from Corsa Touring to Borla Stingers w/dual tips and kept my Corsa X-pipe. WOW!! What a difference in sound. There is a bit too much drone in the 1500 - 1900 RPM range ('98 Coupe A4) but I think with a little insulation or just getting used to it, I should be good. VERY happy with the aggressive sound and look. First thing I noticed on the expressways out here in Chicagoland is that when you back off the gas, there is far less popping with the Borlas than I experienced with my Corsas. Go figure!
The loudest two that I know of would be the SLP Loudmouth and Borla XR-1. Neither one of those have a muffler. I use to have the SLP Loudmouth on mine, that with headers it sounds like a stock car. I loved it but I got too many complaints from neighbors so I changed it to the Corsa Indy Pace Car.