Interesting. I have the same question. I have a 1997 256 and the manual shows a fuel capacity of 57 gallons. However, when I am very near "e" and filled up recently, it only allowed 33 gallons. I can't believe that there are 24 more gallons left when I am close to "e". I suppose that I should also check my fuel sensor to be sure it is not getting stuck somehow. Any thoughts?
Also, where can I find the performance spec's on RPM's, GPH, range, etc?