Is the a way to use datamaster or log data to calculate aprox miles per gallon?

 

uhhh.... you know datamaster has fuel total....anyone....???

 

I was wondering what that fuel total was for



Robert

 

Havnt used datamaster but i would assume that it just adds up the pulse widths and does some calculations to determine the total ammount of fuel flow. If the injector constant and the fuel pressure are known accuratly, i woudl assume that its probably reasonably close to the ammount of fuel used. Youd then take the fuel total and divide by miles driven to get the mpg. Ive done a similar thing with my winaldl data logs since the odometer and the trip odometer are busted (thanks to a fit of rage on my part).

 

the only problem is that if 1 injector is clogged or your voltage fluctuates even a little it throws the whole calculation into chaos.

for instance at 13V your injectors open slower (and therefore flow less fuel over time) than at 14V. so at idle you may encounter really high Pulse Width readings yet only be getting a little fuel because of the voltage drop from sitting at a low rpm.

happens to me all the time. Best way to average fuel economy is to Top it off, drive it, then top it off again and check your miles travelled vs fuel pumped in.