A link to performance details can be found for each engine at the Beta Marine web site under "Engine Models". Look at the bottom of the page on each engine model for the link.
The fuel curves represent max fuel burn at full load.
FYI I have just pased 800 hr. on the 38hp Beta we installed last year. Great engine as you know. We run at 2600 RPM and average about .7 GPH . What is remarkable is that we charge about 1.5 hr per day when on the hook and at about 1400 RPM with the load from the Iskra 100 amp alt we are burning just under .25 GPH . We have been changing the oil at 150 hr and it is still clear! Great engine and perfect marinazation.