[QUOTE=hugo;211864]Bushwacker, what brand 4 blade prop are you running? . . . QUOTE]
I'm running a PowerTech ELE4 15x15 4 blade prop, which supposedly uses the old OMC SST blade profile. It's made in the USA and beautifully finished. I previously ran an SST prop on my old 115 and it was a good prop with a fair amount of cupping. I was able to raise the motor 1 hole and I picked up 3 mph over the same size cupped aluminum prop I had been using. PowerTech uses the Michigan 2-piece hub system with a precision machined metal insert/adapter; the plastic part seems substantially more robust than the Merc 2-piece hub system (Flo-Torque?) which uses a crude cast insert and a relatively thin plastic part with some sharp corners which look like significant stress risers. I carry a spare plastic insert but have not needed it, with about 425 hrs on the motor.
I've also tried a Michigan Apollo 14.125x20 4B prop which also planes at a similar low speed. It's actually advertised as a bow lifting prop, but that extra blade will still produce more stern lift than a 3B prop. It gave me 49+ mph with a light load, but I normally run heavily loaded on long trips and it only turns about 5000 or even less with a heavy load. The optimum rpm for my motor is 5400-5500, and I turn about 5450 with the PowerTech, pretty much regardless of load; it has a much better hole shot than the Apollo. I also have a 4B aluminum 14x20 Michigan Vortex (aluminum version of the Apollo) that I had repitched to an 18 that I use for a spare. It will turn about 5500 but is about 3 mph slower than the Apollo.
The 4B BRP Cyclone and Merc Enertia are also supposed to be good offshore props that will allow you to hang on plane at low speed, but I haven't tried them. The 3B BRP Rebel is also supposed to be a very efficient prop with a large blade area and good stern lift similar to the Merc Mirage, but my dealer says they're normally used on the 3.3-3.4L big block V-6 and the 2.7L small block V-6 generally won't spin them up to optimum rpm on a boat like mine. I probably should contact Ken at Prop Gods to see if he has anything that would beat the PowerTech, but I'm already pretty close to optimum and not sure if I can justify spending another $400 to get just a small bit more speed or mpg! If you come to the Long Point gathering, you're welcome to try any of my props! That Apollo might work for you on that 200 hp motor and I could make you a good deal on it! Denny
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