I remember first doing this back in the mid 70's when gas skyrocketed to over $1.00 and we had gas rationing(remember odd/even?) We used the vacumn gauge to watch fuel economy. It is a great way to monitor your lead foot, and used properly can get you better mileage than using the cruise control. But who wants to monitor fuel efficiency in a sports car? Especially an SRT. And this doesn't tell us if the SGII reads boost in the SRT. My bet is that it will not. Zeitronix may be in my future, but not the priority right now.