Compare the numbers. First realize that torque does the work, not horsepower. The 2 stroke Tohatsu is a 42.5 cubic inch motor, the 4 stroke is a 53 cubic inch motor. I have owned and run both quite a bit. With the 4 stroke, I could run from Hebert's to Grand Bayou and back on about a gallon and half of fuel and ZERO oil.
The 2 stroke pumped 9 pounds of water pressure at best, the 4 stroke pumped 24 pounds at best.
As for performance, the 4 stroke will leave the 2 stroke in the dust on takeoff and top end on equal boats, you can't beat cubic inches.
The 4 stroke is the way to go. When I was testing the Ambush boats for Lake Area, we put a 4 blade 24 pitch cleaver on the 4 stroke and ran a 1548 right at 55mph. That motor would turn any prop we put on it. You would even think about getting on plane with a 2 stroke and a 24 pitch cleaver. The 2.08 gear ratio in the 4 stroke is a killer for hole shot. The motor likes to spin up and run around 6000 rpm. Kyle was right in suggesting the 4 stroke. As compared to your old OMC, you are going from a horse and buggy to a corvette
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