27 Power question
 

OK gurus,
Here is the quiz for the day..:D

Would a new single 350HP outboard be enough muscle to push
the recent addition of the 27 CC?

Yes it will not be a speed demon, but that is not the intent
of this boat.

It will be used as a tender for a 70 Hatteras M/Y that will live
it's life in the outer islands of the Bahama's..

Bring it pro and con..

Thanks..
Attachment 5404

Attachment 5405

I assure you I have no direct answer. But a 300HP Bravo 3 I/O does well with the 25 seafari- ~27-28kt cruise. So I think you are in the ballpark if the center of mass isn't terrible.

edit: clues here: http://www.classicseacraft.com/broch...ure/index.html

http://www.classicseacraft.com/broch...ure/index.html

Max allowable HP 600, wweight 7000 lb, rated for dual 2.6 OMC sea drives (2 x 175hp-200hp) or a pair of real outboards.

Expected dry weight?

Hey Ken, I know of one guy who has a 350 Yami, he says it has one problem.....that V-8 eats gas like crazy. However if you can afford a 70'er you can afford gas for this one.

For sure the 557 outboard by 7 Marine, 557 HP electronically controlled aluminum small block V8!

Did I miss something?? When did you buy that?

Horse power might be adequate, but torque is likely to be an issue. Planing at low speed is where it will show up.

Hey Ken,

My buddy is in the same boat (Literally). Please let me know what you decide. He picked up a 1986 27' Center Console version that is listed at 5000.00 lbs dry. It currently has Twin 1999 Yami OX66 Fuel Injected Engines on a bracket that run fine with less than 400 hrs each. He is going to keep the Engines for the upcoming season, but was thinking of re-powering if he likes the boat. My thought was a single 300 Etec at about 540 lbs. My thinking was my 27 has 350 Diesel HP (At the flywheel, Lots of torque and Huge Props). I have plenty of power for what I do. I can cruise at 30 Knots if I push the Engine to 3100 RPM. I usually cruise at 2700-2900 at about 24-27 Knots and I top out about 35 knots loaded, was about 37 knots empty at 3500 RPM (My boat weighs around 8000lbs). There are few days up in the NE when we can cruise above 30 knots, yesterday was one of them. Anyway, I figure my Engines weighs about 1800 lbs, Engine, Jackshaft and DPH drive. He would have 300 HP (At the Prop) and less 1300.00 lbs of added weight. He is pushing 500 HP, the boat flies, close to 50 knots. Take away another 530 lbs (one 250 OX66) and the drag associated with it, and shave the HP from 500-300, it should have similar performance as my boat, maybe better. I was thinking close to 40 Knots with a cruise around 25-30 with decent fuel economy. I figure the 4-stroke would work too, but just a little heavier. I realize the Engine will work a little harder and will use some fuel, but it should be fine. Not a rocket ship, but decent. He will be taking up to Six Passengers, but just off Chatham and the rips below Monomoy, from Ryders cove and Maybe an occasional Tuna trip in close.

Bottom line, I think it will work. I hope you do yours first (LOL) Good Luck

Second this ^^^^^^

The 7 Marine 557 is a BEAST! Makes the Yami 350 seem like a boy.

Heck Big Money, why dont you just get 2!

;)