Drone was not really an issue for me until I installed FRPP shorty headers (due to a GT40P installation). The rest of the sysyem consist of an off-road H-pipe and Dynomax 2 1/2 Ultraflow cat-back. Here's some methods I've read about to kill drone :1. Install a high flow catted H-pipe, 2. install longtubes (although I don't know if any will fit with the GT40Ps) 3. Install quieter mufflers like Hush Thrush, Thrush Turbos, 3 chamber Flowmasters or even a set of stockers (sorry but I don't have the money to blow on Corsas), 4. install deadhead chambers/pipes on the over the axle pipe to cancel out the drone harmonics. Which is best? The drone is so bad I can't drive the car anymore at 2000rpm.