Hilton wrote:
1. Go on a diet
2. Define a gallon of 100LL as weighing 5.82 lbs instead of the usual 6
lbs - Mooney did it.

Is this legal/valid? If so, why don't all manufacturers do it?

Yes, diets are completely legal and valid and most of us should do so.

Mooney didn't "define" a gallon of 100LL to weight 5.82 lbs, that is
what it DOES weigh. Someone else "defined" it as 6 lbs many moons ago
to simplify calculations. If Mooney is doing as you say (I didn't take
time to verify), then they are just being more precisely correct, if
more impractical for their pilots.


Matt