Has anyone had any changes made to their stock exhaust? My husband heard about a guy in Vancouver who's company re-tunes stock exhausts. We talked about buying a Corsa exhaust but then Todd took off our stock one and dropped it off. We just put it back on our convertible on Saturday and it sounds really good. It was really cheap compared to buying a aftermarket exhaust like the Corsa one we were planning on. Does anyone know if making changes to the stock exhaust would void the warranty? Ours sounds really great but looks completely stock!