Thought I'd seen most merc racing motors from the late 80's and upl. Does anyone have any info on this thing? Did they work, or was it just a prototype deal.

Only duo prop OB I've ever seen, was the Yamaha 150 duo prop.

Oh, and it looks like they where two speed!?

Blackhawk lower unit mated to an outboard?

Never released. Was very trick but don't think it ever worked.
And yes, Yamaha produced a single speed version for several yrs.

That was the "Deuces Wild" wet dream of Freddie.

I heard it was produced, and it did work. It was just way too $$$ to go into the bass boat market.

X2 sure looks like it!

Well dug up a little info here and there during lunch

It's not a BH lower. It is infact a two speed, not in the normal sense, but in the sense that one high pitch prop is free wheeling while the low pitch prop accelerates the boat and runs at lower speeds. Then at a set rpm, a clutch of some kind shifts to the other prop with high pitch, thus making the low pitch prop free wheel. That is some bad azz engineering in a small gearcase like that.

Imagine the prop pitch discussions we would have in the prop forum, if this where the norm Many times we can't even agree on one

first thought that comes to mind here is the low speed prop RPM when its WOT in second?

I had the same thought. But hey, it's a 200 hp ob, how bad can it be? Just think about the 1.35, 1.24 and lower geared props behind 6500+ rpm motors. 6500 thru a 1.24 spins @ 5142. 7000 rpm's thru 1.62 is 4320. It'll be ok

the two speed part of it makes sense to me. There was some success using mis matched props on the Volvo DPX's but at the cost of decreased lower unit life. I would guess having an over or under drive available to one of the props would eliminate this but still allow optimum pitch. Also i have been told (by C Spray actually ) that as a dual prop reaches higher speeds approaching 90? 100? the second prop becomes a drag. I wonder if allowing one of the props to freewheel, as in this case, eliminates or lessens the condition? Cool azz outboard btw wonder where its at