I ran a Wideband O2 sensor with mine and the more boost I dialed, the ECU looked as if it where compensating for that, by adding more fuel. The shop owner and Dyno controller kept asking me to tune down the fuel, because the car was just way to rich to get a good solid number. It became really kinda embarrassing after he kept asking and I spoke up and said I don't have one in the car to tune the fuel yet, I was just coming to see what kinda power the car had.