Part of the problem here is lack of any standard test or elimination of variables (air temp, pressure, humidity, wind).
Might I suggest an experiment? Get some
accurate fuel consumption instrumentation that can tell you accurately the distance and fuel used, do an A-B-A test with just the weight.
- When your tank is low, go to your test loop. A calm day would be best. Car should be already warmed up.
- Bring along enough weight to simulate a full tank, in the trunk.
- perform the loop with a consistent driving style:
- with the weight
- without the weight
- with the weight (like A)
The distance should be consistent between all runs and the fuel used *should* be different without the weight, if weight of the fuel is a factor.
re: vapors, some smart person should probably figure out the equivalent liquid gallons of 10 gallons of fuel vapor too.
yes, I can hit the list buttons too
