Bully Dog began in 1998 as an enthusiast business focused on improving diesel engine performance. Bully Dog is at the forefront of performance ECU calibration technology for gas and diesel vehicles looking to add performance, tackle challenging terrain, haul heavy payloads, or tow trailers over long distances. The straightforward installation, facilitated by our advanced handheld programmers, ensures swift and immediate access to improved performance, enhanced safety, and better fuel economy.