mulliganmagic
Petty Officer 3rd Class
- Joined
- Jan 9, 2004
- Messages
- 82
My grandfather owns a 1983 Norris Craft fish and ski boat. Even though it doesn't belong to me I use it with him every time that he goes to the lake. But the boat has a problem with the ride. Even though it is a fish and ski boat it actually has the same hull as the same length (17.5 ft) bass boat that Norris Craft builds (the only difference is more seats in the bow). It has a 1986 150 hp Mercury Black Max XR2. He runs a 23p Quicksilver prop and it hits about 5500-5800 RPM at WOT depending on the load. This boat is a serious machine and it will run close to 70 mph I would say (speedomitor doesn't work correctly). The boat has a good hole shot of about 4-5 seconds, and yes the bow does shoot the moon. But now that you know the set up our problem is with porposing. We don't run the boat wide open all the time we usually run about 3000-3500 RPM to cruse. However, at this speed the boat seems to porpose a little (one reason for this is because these boats are very light in the front). I guess my main question is would a hydrofoil fix the porposing problem on a motor this big. I have suggested smart tabs for this boat but he said that they are too expensive for that small problem. Also, I read on the forums that for the foil to work right it has to be trimmed up, but right now we have to leave the engine trimmed all the way down until we push it up to at least 4500 rpm or so because if we trim it up it porposes much worse than before. Sorry if this is confusing but I hope that you can help with our question.
