[brucepick]

Goofy1 (Garth),

If your factory mpg computer can be zeroed by you, the GGP will probably accept its readout as official mpg. That is far more reliable than the alternative, which is based on filling up before and after the competition. With the filling station located at the bottom of the mountain, the drive up and coast back down have a significant effect on your overall mpg. And we've seen some really silly mpg numbers from that measuring method in past years.

You should send Bob Gillespie an email, and cc me - so he will know I saw it. Let him know what your car has, and ask that he use that for scoring.

The last two years, Bob has accepted Insight's factory mpg readouts as their mpg score. We EcoModders had three Insights in those competitions, mine, Robert Acevedo's, and Matt Hooler's. The GGP rule applies specifically to cars with "bladder tanks", and Insights don't have that - but they do have good factory mpg computers.

Below is a clip from the GGP rules.
Priuses have expandable bladder tanks which make it impossible to fill them to a standard level. So the GGP had to establish this rule years ago. It's a real plus when applied to any other car with a competent factory mpg computer.

"All vehicles utilizing bladder fuel tanks will use the factory-equipped fuel economy indicator to measure fuel consumption. Green Grand Prix officials will reset the indicator immediately before the car enters the track surface; the same official will read the indicator after the vehicle exits the track."