So my boat is old but I love the ol girl.  It's a 79' glastron hpv 160 with a 115 Johnson sea horse.  Grey and white with silver flake.  Ooo she is sweet.  Well... maybe not comparatively to the rigs of today but I love it anyway.  In August I replaced the transom.   I also did some patch work on the the stringers to get her back on the water so I could fish the rest of the season.  I babied her just to be safe but I'm sure I didn't have to.  In the spring I intend to do some work in this department to get he ship shape.  A few other things and some motor maintanece are on my list also.  I'm way off topic to start but this brought me to thinking about something else.

From my estimations I'm getting about 30 miles out of a tank of gas. I run 93 octane ethanol free gas.  I'd rather run 87 but I can't get that minus the ethanol.  I also have been using stabil marnie with every fillup.  This mileage has been fine for me as I don't normally need to travel far to fish. However, id like to do a little traveling this summer and see some different water.  Does this sound like enough mileage to fish lakes like the NY finger lakes and Oneida lake?  

The motor deffinatley needs a tune up.  It's due for new plugs, wires, and some carb work.  I am sure this would improve my gas mileage a little and would extend my range to 35 miles.  Sound right?

It may be possible to find a tank with a large pr capacity that will actually fit but is it necessary or worth it?  I know there are a ton of variables here.  But consider a normal day of fishing.  Some wide open, some idle, and average conditions.  

How many miles on average is reasonable?   

How big is the tank?  I can't imagine what I'd do if I only got 30 miles out of a tank.

Well... I could be off on my estimations.  And I'm not 100% certain on the tank size but I think it is 12 gallon.  I know that might sound crazy but I've never pulled it up to the pump.  I fill up using 5 gallon tanks. 

Originally this was suppose to be an 18 gallon tank.  But it appears someone swapped it out somewhere along the way.