rhillman75
Petty Officer 2nd Class
- Joined
- Jul 28, 2010
- Messages
- 176
I had a 14-3/4 diameter 3 blade 19 pitch prop that had some age on it (used as back up). My wife decided to "smoke" my 14-3/4 4 blade 19 pitch prop 4 weeks ago in shallow water. The planing with the 4 blade was better (I knew that from comparison), but I decided to buy a 14-7/8 3 blade 17 pitch prop from iBoats that seem to gain a little more MPH (maybe 40 tops) at 4,800 rpm with maybe 50 pounds of gear, 2 adults @ 300 pounds, 2 kids @ 100 pounds. I usually run about 3/4 throttle to keep the RPM down to 4000-4200, but I am losing MPH by doing so. I put the trim tabs on (SX 60 Series) and they did make a huge difference in planing and porpoising but it seem to lower my MPH with them in the stock hole number "3" setting. I know I'm about at max on RPM with this set up but I can still only get about 32 MPH on the GPS. I guess I really do not know where to go from here. The motor is timed, idle set at 700 RPM, ANYTHING and EVERYTHING has been done as far as maintenance... did I get the wrong prop? The boat is a Sylvan V196 (Barritz... I think), with a Mercruiser 4.3LX Gen + motor and the Alpha One outdrive. I keep hearing of "bigger" boats (length wise) with the same motor that get upwards of 40+ MPH. With that said... what should I do? I did not play with the trim tab setting because I did not have time in the water, but I do not think adjusting them is really going to obtain more MPH (but then again... I do not know). According to the manual I am at 180 H.P. with a gear ratio of 1.81:1 and WOT RPM of 4400-4800. Is going above a 19 pitch going to be any better? Any thoughts would be great!