CARB legal supercharger on CARB legal piggyback ECU on a stripped interior and a heavy right foot. I think if I tried, I could probably get 25mpg. But currently, my SUV gets better gas mileage. Lol[/quote]
The supercharger and lightened car should offset each other. Do you know what your current LTFT (Long Term Fuel Trim) is that you are running when @ highway speeds?
I wonder if the piggyback ECU is pulling too much ignition timing when under light loads. Does your engine have variable valve timing?
