Yep, just about 8". Propshaft to crank on a blackhawk = 13.5, standard bravo = 21.75

These are way radical, I'll try and post a drawing later.

the big question for me is where to find more props. I have a drive already and a couple sets of props. can cleavers be adapted to fit?

That's what she said....

8 1/4 lol

Marc how much HP and Tq can they handle?

Does the transom need redone and lower the mounting point? I know some boats are hit and miss with even as little as a 2" shorty lower working well on a standard bravo. So how does it work with boltinf on an 8" shorter drive

Gary Meisenberg Sr. Is the man that did develop the Blackhawk drive. Hes a great guy & loves to talk about them. He had one on his 25 Talon, that I think he still has. He is still around Oshkosh/ Fond du Lac area.

That's the 25 talon I was talking about and yes Gary was the lead guy I think from what I remember. We didn't see them much as we were doing mostly endurance testing and they were doing more as far as performance and seemed to always be switching drives around and props. He's a very cool guy and very easy to talk to. That talon was a hoot and probably the fastest single engine boat I've ever driven.

Hoss propeller will still make props. B3 props can be made to fit with a little machining, but none of those are suitable for surfacing. (but could make for cheap back up props.) If you go the single prop conversion route and build it with XR gears and all of max machine's bells and whistles, you might as well go scx4 and have a drive you don't have to worry about. A billet cap,max machine vertical shaft, and thick floor gears are the upgrades I would get if you plan on anything more than stock black motor. (they have steel tower similar to XR's stock.) Even with that I would think anything past 550-600hp and drive is on borrowed time.(maybe less depending on the boat and driver.)

Yes Gary is great... only problem is if you start talking boats with him, you'll be there for hours & hours & hours & hours.... LOL

pstorti, I'm not sure as I really don't have any experience running them. I think building it with XR gears would put it pretty much the same as an XR, even though it might be harder on the gears because of the surfacing. So I think you will get a lot of different answers on that. The guys actually running them are going to have the best info. I built one for myself with X gears to go behind a 400 HP small block and I don't anticipate any problems at that power. I haven't run it yet however :( too many projects!

dsmawd350, the installed height is critical, there is no way to add spacers like a standard drive. But a Blackhawk is not going to work on every hull. That is one of the reasons Mercury dropped them.

I've talked to Gary also, he is great!

I have always wondered what twin blackhawk drives would do in a 30' catamaran with small block power. When you look at cats in this size range that run surface piercing outboards and cleavers they post pretty big numbers for the power that outboards make. I would think utilizing a surface drive, cleavers, and motors lighter than a big block would be a great package and could run big numbers.

Im running the blackhawks which were said to be rebuilt with the newer heavy duty merc gears by previous owner. Which ones? who knows. I had my mercury certified mechanic take off the drives too check motor alignment and to also go through the drives to confirm what exactly I have and the condition. He said that the drives are capable of 500-550 hp with proper throttling for re-entry. He said drives have heavier duty internals than original (he mentioned x, xr can't remember) He said he had tried these drives in the past with little success. The boats that are known to run well with these drives run very well. I would think the bat boats, scarab P29 might be the boats that have added hp more than some of the other boats that were sold with them. Im thinking a couple formulas had them also. Biggest issue with these drives is the lack of quality props or any props for that matter. The merc props are the only ones that seem to stay together. Early testings with some aftermarket props would throw ears off of the prop. I have heard of mix and matching the 3 sets of props, 27, 29, 31 for fine tuning. Not much time was spent on this part due to the hawk project being discontinued. Which also stopped aftermarket shops from R/D. Hoss props and also cleaver made props in the past. I do feel their is a following for these props and drives but probably not worth any large investment due to the low numbers of people actually using them compared to the money that can be made from the current bravo setup.

I've always wondered if the hull on my non step 93 fever would run good with a hawk on it. Always wanted to try it. I know the 242 formula and the 272 ran good with them as well. But we did have big thick aluminum adapter plates for the transom with different drive heights to fine tune it but the one that was on it when it showed up from Stillwater had the best performance so we never changed it.

I have a 20' Cig with an Ilmor 625 Gen III on an ITS Transom Assy with a BH drive. The drive has been rebuilt with XR parts and runs mint! I have at least 60 hours of run time on it without any issues and I run the boat Hard! Obviously my boat is not particularly heavy but with 625 hp the drive has held up nicely. I love the way the boat handles with it.

There is a spectre 30 with small blocks and single prop blackhawks out there somewhere. ( I saw it for sale at one point)

I think an LS blackhawk package would make for light and efficient combo, You could get down to near verado 350 weight and still make 600hp

I have a set of 31" pitch Merc props if anyone needs them. One, I believe has never been run and the other is low hour but has a small ding in the leading edge.

How much are you looking for.

Great drive and cool looking piece ,here s a video of one I tried on my 21 ft LS powered toy but too bad it didn t work as the hull not have natural bow lift and the boat run very flat but still did 95 mph .

and love the rooster !

http://youtu.be/Dh1AVt_vc28

here is that spectre 30
http://www.powerboatlistings.com/view/12781

They said it ran 103 with the pro chargers. I bought the engines off them in last month. Took all the procharger stumm and I am building a pair of 383s with components.

Is that hull and drives for sale?

Hull was for sale in classifieds here on oso

Sounds like you guys have some great projects going on! Years ago I did some testing with the hawk on several different boats. One was a 24 fountain cs. We gained 8 mph on it just by installing a blackhawk on it. I'm in the process of building a hallett vector with an its and a blackhawk. I have two setups for the hawk. One is a # 3 shaft and one is the stock counter rotating configuration. Hopefully I will have it finished this summer. I'm also considering having a custom # 6 style propshaft made which will allow more prop selection

8mph and that roost? This has my attention.

That 20' Cigarette sounds great from you described, please post some picture of the boat, motor, and drive, that is one very boat you have with the power and drive, to me it is very desirable and very f*cking cool!

Pretty sure this is that 20 cig http://www.lipship.com/posts/view/19

750hp cig 20 Blackhawk https://www.youtube.com/watch?v=UEbO6tra5to

Probably the best video to see a blackhawk in action, that was posted in the past https://www.youtube.com/watch?v=VbSZ7BM2rEE

Bob leach used to put them on his 22 Daytonas with 502's in them. They ran just under 100 bone stock. He did a lot if testing for mercury with them. It was his idea of having a 2 speed trans that prompted mercury to design and build the black trac transmission. The only downfall of the blackhawk on the Daytonas was getting on plane. The 2 speed black trac transmission was mercury's answer. The problem with that was space. With the correct setup these drives are amazing

Yes that is my 20 and I did the video as well. The red 750 boat is a friend of mine.

Blackhawk Roost[ATTACH=CONFIG]521593[/ATTACH][ATTACH=CONFIG]521594[/ATTACH][ATTACH=CONFIG]521592[/ATTACH][ATTACH=CONFIG]521595[/ATTACH]

Pictures 2,3: that rooster is incredible on a P29. Trim has to have been up very far. I love it. I wish my rooster was that "Big".

Do drive showers work on the Blackhawk?

I don't think they are very effective if the pickup is on the cavitation plate. I think the best way to do one is to have a water pickup on the hull routed to the drive shower.

Anybody have any idea what a Blackhawk with fresh uppers and decent 29 props is worth these days ?

Had one on a 22 Donzi Classic. I remember it being good for 7MPH on that hull. Sounded like a blender in the back with the props surfacing. Props moved a bunch of water at idle and made a good sized wake in no wake zones. Great drive!

Wish I had a pic of the white and tan 24 or 26 foot cobalt that we tested a blacktrac trans in. The merc guys slapped a hawk on it one day and brought it over it was tripy watching that thing plane like having a bravo on it grabbing high gear and the roost start growing at almost the same time. It was diffinitely cool.

I have an offer of $800.00 and the buyer will pay the shipping.

I would give you $1000. Would really like to have an extra set.

I liked the Blackhawk when it came out, with dual prop for the single engine boats which is good engineering. What about this drive too? I know very little about it but seems provide the same function, dual props, not sure of the cost of this surface drive, the Weisman Hammerhead. I have always liked the engineering in the Weisman products,and the notion of creating new products, and the same can be said for the Blackhawk becasue when it came into the marketplace it was different, innovative, I like new ideas or existing ideas that have been re-engineered to work well.

https://www.youtube.com/user/weismannmarine

http://www.weismann.net/press%20page...annduoprop.htm

That is a sweet lookin surface drive.