I scanned all the replies and you got a lot of good, accurate info. Problem is you are under powered............... period. All the wishing in the world won't solve it. You want you cake and eat it too.....you want speed and pushing power simultaneously and under powered you won't get either. But you can cut the pitch of your prop, as suggested above, and help your engine survive and run better and cleaner in the process.....but don't expect any increase in speed....decrease is what you will get in your situation.
My rule of thumb and others have agreed in non related separate postings is that 2 strokers need to spin up. Horsepower is (torque x rpm) / 5252. If you are shy on cubes as are a lot of 2 strokers you don't have adequate torque.....cubes make torque....check the big rail dragsters....big block v8s....lots of cubes, lots of torque. Small blocks can't stay up with them....Hot Rod Magazine. Another problem with 2 strokers and lack of torque is the fuel scavenging process. Half way through the power stroke you open up the exhaust ports and let out all your, what's left of, your combustion whereas an under square 4 stroker will burn down the full length and just keep pulling and do it with much lower rpms.
Merc flaunted 99 cubic inches back when they boasted 1 hp/cu in in the Merc 1000 and continued with that sized block up through the 150 tower (Inline 6). It had to run up the rpms to get it's hp since it didn't have the cubes. The V 150 comes out and is a 2 liter at first. Couldn't get the big bass boats with their 3 batteries, 50 gallons of gas, pair of 50 gallon live wells, 100# of tackle 2 big butted fisherman, 500# of engine and 2000# of boat out of the hole (on plane) in a reasonable length of time. So what did Merc do? It came up with a hot dog 150 and guess what.....it had 2.5 liters of displacement. Did make a difference.
Back in the '50's OMC had a lowly 25 hp that ran at a leisurely 4500 rpm but as I recall had 35 cu in of displacement. You could put a 16' plywood boat in front of that with a couple of fishermen, 12 gal of gas, one battery, a livewell, some tackle and run across the bay at a 20-25 mph clip. It had the cubes, didn't need the rpms. Course the rest of the story was that those plywood boats were light and had a very slight semi V. Most of the hull was almost flat which made for a nice, easy, planing hull; beat you to death in a chop, but planed nicely with low hp engines which is all we had back then. Back then you never saw a tach so nobody knew whether they were propped properly or not.....just ran what came with the engine when new.
So sir, get your 8 pitch and be satisfied with it or get you at least 75% of your BIA hp rating engine hp and be on your way with speed and great hole shot.
