Not impressed - 350 b3

[gueretma]

Since having the 260, I really like the boat, I am somewhat disappointed in the cruising speeds/rpms of the current engine. It has a 350 merccruiser bravo 3 which has been a little less power than I was expecting. Is it possible upgrade to a higher end engine like the 496 Magnum Bravo® III MCM* (375 hp - 280 kW) or something even more impressive. Could anyoneone give me some options.

currently im going around 24mph at around 3800-3900rpms

[yottyboy]

Adding a Vortech Marine supercharger will gain you another 70 odd horsepower without replacing the engine. That will allow you to spin a pitchier prop. Same thing with a naturally aspirated big block. If you go with the big block, the advantage is that it gets into it's horsepower band at a much lower RPM. That way you spin the pitchier prop at lower RPM. If you were to supercharge the big block, it will be able to push the largest props you can fit to the B3. If you go with something like the World Products Merlin block, you can get it in sizes in the 800 cubic inch range. Same with Donovan's engines.

[IslandTrader]

Well if you pull your current power plant and drive system, I may be interested in them for a boat I am rebuilding...smaller and lighter.

Let me know,

[Erie Skipper]

Sounds to me like your props are entirely wrong--see a prop expert or good marine mechanic That 350 mag is 300 hp and should turn closer to the 5200 rpm range if I remember right; or at least high 4000's Maybe on of the props has a spun hub? You shouldnt need a repower and Sea Ray is not in the habit of building underpowered boats.

Your local dealers should be able to help you.

[ihateboats]

that's a whole lot of boat for 300hp. I've got the same motor/outdrive in my 24'. It does well, but no hotrod.

[IslandTrader]

You shouldnt need a repower and Sea Ray is not in the habit of building underpowered boats.

I have heard just the opposite, there are a lot of underpowered Sea Rays out there. The main complaint of the owners are they sea trialed the boat empty. Bought the boat, loaded up all there gear and family, and the boat never performed like the sea trial.

So I think there is truth to both sides of the story.

[prober]

I have heard just the opposite, there are a lot of underpowered Sea Rays out there. The main complaint of the owners are they sea trialed the boat empty. Bought the boat, loaded up all there gear and family, and the boat never performed like the sea trial.

So I think there is truth to both sides of the story.

What is your WOT RPM and speed? It sounds like you gave us your cruise speed and RPM.

I would think that a 26' sundancer would not cruise much faster than that with a 350 mag. That size and weight of hull is solidly in twins territory. A big block would help but I think it would be cheaper to just trade for a boat with proper power.

On the Sea Ray website they show the 350 mag as the smaller engine package. They also offer a 496 with 375 HP and a diesel with 300. I don't think the 496 would be a rocketship either since it is Not that big a jump in power but the extra torque would help and the engine would be working easier. Might cruise closer to 28 though.

At an additional $13,000 to build the boat that way I would think it would be too costly to RandR.

[Erie Skipper]

I say again, a 350 mag in this boat should be fine if you are propped correctly No it doesnt need twins, and at 8 1/2 beam couldnt even stuff v-6's in there. With the lift of the duo prop and 300 hp, you should expect a top end in the range of 35 mph with an average load. I'm sure if you consult Sea Ray, they will rate it at least that fast.

Is you boat bottom fouled? You'll lose at least 10-20% that way. Give us some more input. Were you wide open, did you trim the drive properly? We need to know more in order to help you.