Had a 290 Volvo drive on my 20 Bertram - great drive and really liked it but kept popping trim hoses - very expensive parts. Also not great over 50 MPH - the profile of the lower unit caused root cavitation on aluminum props so I had to put on a nosecone. Bravos had not come out at that time and, with the cone clutches, the 290 was way better for me than the Alpha in spite of its minor hose problems.
Put a couple thousand hours on an early Alpha - decent drive but the shift interrupt was always problematic and an Alpha is torque limited to about 325 ft-lbs which is about 325HP on a SBC.
In the late 90s Merc came out with the Bravo - it has the cone clutches and pretty much copied the good features of the Volvo 290 - they upgraded it about 2005 to the 'sweptback' design to fix problems with the gear floors and some other stuff that was breaking in the 500 ft-lb range... They are now the entry level drives for racing. Imco, Konrad, and a few others are the higher end.
I got a sweptback Bravo 1X for my 23. If I was getting counter-rotating props I would get a Volvo. The Bravo 3 is the Merc version of that. Counter-rotating props are apparently better at cruise and worse at high speed. I got a great deal on my Bravo 1X and was worried about cost of replacing 2 props if I hit something. I will try to make up for a few percent in cruise economy with engine choice after I get everything else done with.
At the risk of degrading this thread into yet another Ford vs. Chevy vs. whatever, that's my $.02
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01-12-2017, 07:43 PM
Hybrid Mode
