283CHECK

Ah, the more questions I ask the more I think I might want to pass on this boat. Could be the reason they have been sitting on this boat for awhile??

Thanks for the input all

Niuhi

I would think that allot of it too would have to do with the hull design, correct me if I' m wrong. It's my understanding that for example the Donzi Blackhawk is much faster with them than when people switch them to Bravos. One drawback is that with the speed comes some Flightiness. Kind of a trade-off. I would find out what the manufacturer recommends as they know what the hull is best suited for.

283CHECK

The President of the manufacturer said that he would have bravos put on if I did not want the blackhawks but it would slow the boat down. But then again this was the president and not the engineer!

cigarette1

Sounds like a bunch of Crap .... find another boat

Lake Front

I recall seeing a previous post on the black hawk drives that indicated speed at idle (ie. docking) was 3-4 mph higher than with the bravo drives. This may be a consideration with the wife or other drivers. But the down fall is the reduce top end speed by switching to bravo's.

FYI- Back in June or July 2001, Powerboat had a reader that wrote in a similiar question regarding this topic for the 1996 limited edition Scarab P29 - - - As I recall, Powerboat stated that very few manufactures (with the P29 as an exception) rigged the boats appropriately with the blackhawks.

I also believe that swithing from the blackhawk drives to the bravos is relatively simple, since it involves no modification to the transom.

I also believe that the Black Hawk drive was only available in 1996.

283CHECK

And that happens to be the year of this boat It is a 96 Challenger anyone have any good/bad besides the blackhawks on a 33' Challenger?

Cord

iTrader: (2)

I don't know if it's a bunch of crap. I think the mfr is right in that the boat will slow down-for sure 8 mph. The trade off will be a cheaper drive to repair and prop. The boat proably won't be as stable on the top end, because it will have fewer blades in the water. But the skeg will be deeper and that may compensate enough. The gain is that it may be slightly easier to handle around the docks. Those big props really get the boat moving quickly. But the extra blades may make it more directionally controllable-not sure on that one though. You said that it had 502's so I'm assuming that the boat is a older model that came with the drives originally. This means that the mfr proably designed the hull for that drive. I say take the boat out and drive it. See how it handles and docks. I think alot of people are scared of the blackhawk because it's an unknown. Some people also say that you can't get parts for them. Well, merc hasn't made parts for the TRS for ages, and yet they are readilly available. Personally, I wouldn't let the drive scare me away from the boat.

Miss Bud

283 CHECK..........I had a 1994 - 22' daytona which is the first year the blackhawk come out. It was a 502 efi 415 hp and it did well with the stock power. However, after I come up with 540 efi 640 hp or so, it created problems. At idle speed it would run 7 to 8 mph and with the extra hp, it would die on you when you put it in gear.

Goodfella

To answer 283check's question the boat will loose speed with the Bravo's becaues the X dimension for the Blackhawk is much higher. The propshaft of the Blackhawk is much higher than the Bravo I propshaft. The driveabiltiy of the boat will be the same and will be better with the blackhawk at high speeds becaues of the two prop design. Sterndrive reliability will be fine as long as stock Mercruiser horsepower is being used in front of it 502 MPI maximum.

Gordo

Goodfella is almost right on.
First, physically switching the Blackhawk to the Bravo 1 is pretty easy. In fact, the boat I did the switch on was a Challenger.
Next, props for the Blackhawk are not cheap, and you now have 4 custom stainless props to worry about. If you dink one, I don't think Midwest propeller is gonna be of much help. After all, it didn't come off a bass boat.
The X dimension, being the centerline height of the drive input shaft at the transom, should be slightly higher on thie Blackhawk boat than the same boat with a Bravo 1, (per Mercury).
As Goodfella stated, the Blackhawk lower case is also shorter, which in turn raises the propshaft height up even more and brings it to a "surface peircing" level.
Still with me?
Ok. So, if you have two identical boats that were each rigged to Mercury specs and recomended heights for their respective drives. Boat "A" with Bravo-1's, Boat "B" has Blackhawks. Then exchange the Blackhawk drives for Bravo-1's on boat "B". Boat "B" should end up with a prop shaft height of about 2 inches higher than boat "A".
Piece of cake, right?
As for handling, the Blackhawk doesn't really seem to get very efficient till about 45mph or so, (on the Challengers anyway). Below that speed the boat felt kinda sloppy, but get around 50mph and they really start to shine. They are a very "loose" feel at speed, but that "loose" feel is also what gains you that extra speed. Remember, you have twice the props, but only about half of each prop is in the water. I would expect to loose anywhere between 5 and 8 mph by switching from Blackhawk to B-1's.
If I remember right, Nigel Hook &/or Craig Archer ran a 26 Scarab with a Blackhawk and got some impressive speeds with it. I've heard it was a really wild ride though. I also heard they went thru a lot of drives. If either of you guys are reading this, please help us out here.
Bottom line is, I think the Blackhawk was discontinued due to a somewhat high failure rate.
Well, that's what I heard anyway.