Just a guess, but it seems to me that if a V20 and an 18 fisherman both have the same amount of flotation, then the 18 would have a greater capacity simply because it has less weight due to no superstructure. Like I said, it's just a guess, but it seems logical.

I just re-read all the posts in here. I never needed the trim tabs. No porpoising issues at all unless you overtrim the motor.. But they are nice and should have been original equipment IMO.

Good to know on the trim tabs. How much setback is your bracket Ridge?

Stainless Marine 30". Moved fuel tank and console forward a tad and installed a 13gallon fresh water tank in the dead space under the floor in front of the fuel tank bulkhead, moved the batteries under the console. The modified console is a heavy SOB, despite the fact that I cut off the bench seat/storage off the front and use a 94 QT Igloo in front of the console as a seat. IN other words I tried to adjust the balance of the boat to compensate for the 30" setback. It works best with the 400 lb motor it was intended for, not ideal with the big motor.. 24" to 26" would probably be better.

Gotcha. I was thinking about moving my fuel tank forward, but not 100% dead set on it yet. I also have a water tank from the Sportsman. Plus one 27 gallon tank, maybe one more if i can find one for a good price. I was actually planning on installing the extra fuel tank in front of the stock tank. But i have a thru hull fitting with a water pickup about eight inches from the cabin bulkhead. I will have the cap out of the boat so its easier to do any modifications. But i also want to foam any unused areas. If i use the water tank it will be in the cabin. All the way forward.

I believe that is true, but it is proportional to the hull length. A 30 foot boat can take more setback than a 20 footer.

If you study the "go fast" guys, they seem to like around 24" of setback on a 20' boat...and they have tried everything to get 1 more mph out of their boats.