not too much louder at idle or cruising, decently loud under WOT - known for minimum drone... do a search on the viper forums , you should be able to find more info than you can handle. www.viperclub.org or www.viperalley.com
+1. What Outlaw said. There are louder out there...but the Corsa track is only loud when you want it to be. Now me...I go for Mopar Street with no cats. Very LOUD.