I picked up 100-200 rpm. Maybe 1mph. I have lighter weight smaller boat. Hammer's are only 22' and about 3500lbs. Looks cool though. CRMAX, take those plastic covers off off your engine. It will help it run cooler. The MAG versions don't have them (obviously for a reason).
if I pick up 50-100 rpm Ill be very happy, the plastic cover was never on it. jimgoog our boats are very close, mine is 20'1" 8'1" beam 3400 lbs 21 deg deadrise so I would think I should see close to the same results that you did. the biggest differance I can see is a 1 deg differance in deadrise which would make me run a hair slower than you in flat water
Mine really does not run that well in flat water, to much chine walk at high speed. I like 3-4' chop, much more fun to drive in (passengers don't like it much).I have tabs but don't see the need to use them unless I have some friends on board and need to smooth the ride out. The chine walk is easy to steer out of but the hull likes a little air. It defintely cleaned my transom up. I don't know about fuel consumption, when the tank gets down to a 1/4, I just re-fill it.