Being the perennial rain on your parade, I wonder you're 10 minutes of coding away from a data logger. Can you store a rolling last X minutes of run time? If so, how might you keep track of engine hours (key switch on, tach above 200 rpm, oil pressure above 0.5 psi)? Can you overlay date and time and GPS info from the HTC? Is the instantaneous difference between fuel flow from and to the fuel tank a reasonable indication of fuel mileage? A MAP on the VCV output line approximates throttle position, right?

Sixto
87 300D