Biggest fuel tank on 20ft
 

What do you think is biggest fuel tank you can install in an 88 20ft cc without sacrificing performance. Currently runnng a 40 gallon.

My `89 originally had 70 gal which is 5 inches longer than the coffin cut out in the deck...

65 now.
You could go a tad more than 70, if you eliminated all foam, but the rigging oval
will drain down the side of the coffin starboard side.
My tank failed there, not on the bottom.

I think it's important to note what engine is going on the boat and fuel usage.
I had a 20 with a 46 gal tank and an OX66, it was not enough fuel for what I used it for.
Then I did a 20 with a 70 gal tank and a F200 i4, it was too much fuel to carry all the time.

Ole makes a good point! Both Sandy and I have the need for as much fuel capacity as possible because our engines eat fuel like Rosie O'Donnell eats food! In my case my present 144 gallons is OK to supply my pig EFI engine, however if I had a four stroke or G-2 eTec I'd prefer a 100 gallon tank.

What motor are you running/going to run?

I'm running a 4 stroke Yamaha 150 on it

I rudely puke fuel on the troll.

I went up to 50 on my resto but i have a new 115 merc 4 stroke

Only 40 gallons would make that a super priority for me to rectify. I have a thing about running out of fuel. My tank is labeled 107 gallons, apparently installed around 2004 by a prior owner. Runs about 45mph fully filled at 5400 rpm and seems to get up on plane fairly easily.
I thought it wouldve been very difficult to stuff a 107 gallon tank in. Lotta work and mods to stuff 144 gallons in there!