My tuner took about 2.5 hours and 5 dyno pulls to dial it in the programmer is whats used to dial in your air fuel ratio along with your timing for optimal performance do not skimp on a good tuner if it comes to saving a few bucks cuase it can cost you an engine if not tuned correctly also the gauge was easy to install hardest part was welding in the wideband bung in the exhaust for the gauge