Lake Michigan is about 580ft above sea level. Probably 590ft in the 1980s since the lake levels have dropped as of late. I am not sure where Carver does their testing, but they are not that far from Lake Michigan (Green Bay).
Theoretically, the best fuel mileage for any boat is at hull speed ( HullSpdKts = 1.34 x √ LWL ) , and while I don't know what the LWL length of the boat is, a 30ft boat means that the hull speed is somewhere around 6mph, which the chart seems to agree with.
Guess if gas gets above $5 per gallon, we'll all be running around at 6mph.
I still want to put fuel flow instrumentation on the boat, but (at least) with Cruisader's '90s era engines, the EFI used a closed loop fuel system (return line to the tank). This takes a two-stage fuel flow instrument so that the return metering can be subtracted from the input metering.
Unfortunately, there are not many fuel flow instruments that can handle this. But Floscan is developing a NMEA2000 sensor to do diesel (which is kind of the same as a closed loop system). I have talked to Floscan, and they tell me that their system should work with Crusader gas closed loop systems. The fuel sensor system should begin shipping this spring.
