I cry when it goes below 30mpg
That means either the engines gone duff, or has recieved an undue thrashing
Though TBH anything more than 45 is also a cause for celebration. It seems to live happily in the 40-zone. Very odd. Probably to do with driving style... generally accelerating around the torque area at full throttle on every take off (yeah, think I need a more powerful car!) and then crusing
normally cruising at 70-75 mph - anything over that and the thing chews through fuel!!!
Well, speed = negative economy after all.
If we consider:
Power needed at 70mph - 27.2hp
Power needed at 80mph - 35.5hp (approx
)
and at 90mph - 45hp
Power is energy used per second, wheras your speed is distance travelled per second - if we assume that the engine is pulling the same amount of energy out of each gallon (unrealistic but bear with me), then it follows that you can work out gallons per mile from that... or, miles per gallon.
Assuming mpg at 70mph is, i dunno, 40mpg...
70/27.2 = 2.57
80/35.5 = 2.25
90/45 = 2.0
40 * 2.25 / 2.57 = 35mpg
40 * 2.0 / 2.57 = 31mpg
Hmmm not so big an effect as i'd hoped, but you can still see economy at 90 = 3/4 that of at 70mph, and in real life it should be worse still as your engine is operating at a less efficient speed.
Er.
Really can't work out what's wrong with it, I'm sure I should be getting more out of it.. All I can think of is that the carb needs a retune, but I'm sure that wouldn't affect it so badly..
