Repowered in 2018 with Suzuki 300. Currently running a 3 Blade 16in 19 pitch Solas prop. Whole shot slow, more top end than I need. 55 mph WOT @ 6500 rpm. Rough seas a problem. Either I am going too fast or too slow to stay on plane. I was told a 4 Blade prop could help. Just don't know what size to buy. I live in Brevard County Fl and have not found any dealers that will let you sea trial a prop before buying. When coming out of the whole, motor trimmed down and full tabs down, wants to stand up for a good while before the bow comes down, need more lift.
Approx weight 7500lbs Length 24
If you read Solas published literature on their 3 and 4 blade props, they tell you point blank that the 3 is made for bow lift needed in fast running, light hulls, and the 4 is made for lifting the transom when midrange operation is preferred. Yes the geometry of the two series of props are different. I just put a Solas 4 blade on my boat so I have BTDT and yes the midrange control is much better than the 3 Mercury Laser II.
Solas isn't ported (holes under the leading edge of the blade) but due to the geometry of the prop, there is a lot of slippage built into the prop at lower speeds, giving better control than would be if ported....BTDT too with Hustler and Mercury ported props. The thing about prop slip at lower speeds is that the engine isn't lugging under load at the lower speeds. With a reasonable amount of prop slip (25-15% slow to faster speeds) it allows the engine to stay up in the power band and when waves and troughs are encountered, there is less change in engine loading making for more even thrust and a more uniform boat performance. (my opinion based on BTDT)
Big guns frequenting this site over the years, recommend dropping an inch of pitch for the additional 4th blade as efficiency drops as blades are added (2 blade is the most efficient and Merc shipped OEM engines for years with them). Only when they changed from Sea Foam White to Phantom Black (forget the year) when they came out with their Merc 1000, first 100 hp outboard did they go to 3 blades.
So sir, my best guess is hit the Solas 16x17P 4 blade. That plus the correct operation of your trim and trim tabs should get you where you want to be.
My 4 blade has the rubber hub (standard for these props I suppose) which I like over the plastic/brass insert for negative reasons you see published on forums, is made in Taiwan and is of the highest quality in materials, processes and workmanship.......plus my 13x19 was only $275......beat that!
Off topic comment on Caravelle. Back in 1972 I bought a new 18' open bow tri-hull (the popular boat of the era) Caravelle with a 125 Johnson. One beautiful, functional, extremely well built and soft riding tri-hull (when tri hulls were said to be rough riding). Family had years of thrills with that boat. I see they have survived the test of time....I define that as building a quality product.