Just a pipe dream....

**Steven Vaccaro** · 11-22-2008, 11:34 AM

They work great on big heavy boats. Mostly they are used on underpowered boats. It tremendously increases out of the hole speed and lowers planing speed.

Merc put out the blackhawk drive in the 1990's. It was impressive looking and was fitted to some 80mph Donzi classic boats.

**Ocean Racer** · 11-22-2008, 10:22 PM

ok i got in a few minutes age and just finished looking at the outdrive. The prop closest to the hull is a right hand rotation. The farthest prop has a left hand rotation. From my understanding it lessens the amount of cavitaion. Just like Jeffs post say it does give you a boost.

**obrien** · 11-23-2008, 01:12 AM

on the Bravo 3, the front prop is a larger diameter than the rear prop. Also on mercs props for these drives, the diameter changes with the pitch. the lower pitch props have more diameter than the higher pitch props. this application is great for heavier slower boats that what you run a bravo 1 on. the extra prop helps greatly on midrange cruising because of the increase in efficiency. The down side is in the high performance arena.

Mercs blackhawk drive was only made for 2 years. the drive created so much stern lift that most boats had to be build specifically to handle that drive. Donzi had to add rocker in their hulls to be able to use that drive. The drives certainly worked great in top end performance, but was not very reliable. the twin props created alot of load on the drive. We tested this drive on a boat at work no long ago, and it was a bastard to get out of gear. It acutally needed the shift interupt feature that is on the alpha drive so that you can shift if properly.

when it comes to performance sterndrives, (outside of the expensive stuff) the bravo 1 is the way to go.

I am a big fan of the Arneson drives, but there is something about the merc #6.

**Darin Jordan** · 11-23-2008, 02:47 AM

Originally posted by obrien

when it comes to performance sterndrives, (outside of the expensive stuff) the bravo 1 is the way to go.

I like the sound of that and couldn't agree more! Mine seems to get the job done behind the 330hp 454 Alpha...

Now if I just had the time and $$$ to swap out the 1990's Quadrajet carb for a nice modern Fuel Injection setup...

Attached Files

**obrien** · 11-23-2008, 11:02 AM

yeah if you bump the horse power much, you will certainly need to move up to a bravo from that little alpha. Nice thing is the transom assembly fits in the same cut out as the alpha

**Ocean Racer** · 11-24-2008, 01:03 AM

when my dad upgraded his 24 skipjack he used volvo. the original top speed was around 25 26 knots and i think the original motor was a v6. When he upgraded to his current Volvo Penta he went to a V8 and picked up a 10 or 11 knots and a mile on his ngp (nautical miles per gallon). If you are going to use it in your boat make sure volvo will cover the extra X amount of years maintanince. we had a problem trying to use that service that supossedly volvo covered when actually some other company was offering the extened warrenty.

**Darin Jordan** · 11-24-2008, 01:36 AM

Originally posted by obrien

yeah if you bump the horse power much, you will certainly need to move up to a bravo from that little alpha. Nice thing is the transom assembly fits in the same cut out as the alpha

Actually... the outdrive IS an Bravo 1... For some reason, the motor sticker says "7.8Liter Alpha/Bravo 1" on it... but the outdrive says "Bravo 1"... I always just assumed that the motor was the "Alpha" part...

I'm more interested in the F.I. for the ease of starting and the smooth power and reliability... This darn thing starts and acts like an old '69 Chevy with no choke!