What's better for 2820: Twin 150 or 300/350 duoprop?

[afitzray]

I have a 2820 that either needs a lot of work on the twin Yamaha 250's or a new power set up. I don't have far to get to my spots and I don't need to get there at 50mph so I've been interested in the twin 150 setups I've heard about in this thread 150s on a 28?

A lot of folks want max HP in every scenario but for the moment I'm just interested to know how twin 150's would act versus a duoprop 300 or 350? Whether on this boat or a different one, how does the same horsepower act different between twins and duoprop?

A second question I have is if a 30" single can even work on a 2820 with a bracket that's already running twin 30". Is a single in the middle of the bracket going to run too shallow no matter what since it's now behind the bottom of the keel?

Thanks for any input.

 

[pelagic2530]

I doubt you’re going to get much in the way of real-world feedback as I don’t think what you’re asking has ever been done on a 28’ before.

That said, I used to work on a 28’ Maycraft CC with twin 115s. The power was adequate at best for how we used it, which was usually about a 10 minute ride away from the marina. Remember also that that is a way lighter boat than a 2820.

 

[warthog5]

I don't need to get there at 50mph

I think you have missed the point of other conversations.

A under powered boat is a Pig! You have to run the Stem Winding Crap out of the engines... In doing so....your fuel mileage goes to crap.

The bigger engines will cruise at a Lower RPM.....not in a strain and give you better fuel mileage.

One boat in particular comes to mind in my area. 19ft Cape Horn....Powered with a 130Hp engine.......It's a Pig!

That boat needs a minum of 150Hp.....and comes alive with a 200.

I did a bunch of work on one.....Then got a call as to why it would barely get on plane.
They had 2 adults and 3 or 4 kids on it.

The first thing I asked.......You filled the tank slap full didn't you? "Yes".

Under powered and excessive weight lead to a Ill handling boat.



Because you have that Power.....doesn't mean you have to use it.....But if your coming in a rough inlet......It can save your life.......Also.....Running from Bad weather.

 

[afitzray]

warthog I've gotten a lot of great info from a lot of your posts so first, thank you. And I get it that it's better in a lot of situations. I'm just thinking it's not necessarily every situation, possibly including mine. No inlets. Fishing spots are no more than a few miles away so mileage is not a concern. From the other thread "run great with the 150s, tops out at 36-38 kts and used easily 40-45% less fuel compared to the twin 250 boat." I'm pretty much never needing to hit 36 knots so I wanted to explore the idea.

And I was thinking outboards like to get a fair amount of use around 75% throttle? If I can save 20,000 on a repower and get engines that will be run more in the mid range rpm rather than rarely breaking half throttle, isn't that better? And with a lot of hours trolling I thought it would be good.

I think I've decided the duoprop isn't going to work though. I don't see how to get it low enough to work with the depth of the keel.

 

[tomc585]

Something to consider when making this decision is the potential future resale.

 

[Realtor]

Thats a BIG boat for twin 150's

 

[plumsal]

I have twin 150s on a 2510 and it’s enough. Moving up to a 2820, can’t imagine 150s would be enough - I would be thinking twin 300s.

 

[A-K]

Don’t do it. You’d be better off in a smaller boat then trying to push that boat with twin 150s.

 

[Billyjack20]

warthog5 hit the nail on the head about needing power at rough inlets , if you need it you'll be glad you have it .rough seas also.

 

[Key Largo]

Don’t do it. You’d be better off in a smaller boat then trying to push that boat with twin 150s.

I know someone with a 26 ft Proline that he repowered with twin 140 hp Suzuki. The boat is Dangerous. Takes forever to get on a plane. 5000 rpm 28 mph. The boat will broach someday trying to enter the Boca Raton inlet on an outgoing tide with a 15 mph east wind. Almost broached my 1967 19 ft bow rider Seacraft 50 years ago not being aggressive enough keeping up on the backside of the steep waves thru the Port Everglades inlet.

 

[BradH]

I like the idea of twin 300/350s, boat should fly...

 

[Key Largo]

I like the idea of twin 300/350s, boat should fly...

Google, "Jupiter Inlet Boat broached" there are several hair raising video's, 1 was captured by a drone.

 

[Legal Bill]

I agree with what others have said above. I won’t repeat those points.

Keep in mind that the old Yamaha F250s are generally considered to be underrated and really generate around 265-270 hp. You’ll be taking a very big step down.

If you are dead set on smaller engines, look at 4 cylinder 200s. They will be a good deal lighter that the old F250s and that will make up for a portion of the power loss. And they won’t effect the resale as negatively as 150s will.

 

[John D.]

Most if not all of this advice, unfortunately ignores the actual performance sited by the link in your post. Boog states that he actually owned 2 2820’s with 150’s and they performed fine. Based on the fact that many of the 2520’s have twin 200’s I would think that would give you similar performance as the hulls are very similar and as Bill said may help with resale.

 

[afitzray]

I appreciate the input from everyone. I hope to find out if I'm rebuilding or repowering in the next couple weeks. If it comes to a repower then the middle of the road option of 200's makes sense to me but it may just come down to what's available.

And the Haulover Inlet videos are great, make me thankful we don't have inlets where I'm at.

 

[Lucky John]

Do yourself a favor and go with twin 300's. On a side note the Zuk dual prop 300 is $$$, looking to find n engine now, found one in Florida and it was 34 with all the rigging and props.

 

[sydngoose]

I had a 2830 with twin 225's
Yes, it was a little heavier w/ the extended cabin. But, that boat was a fuel pig, and that is why I sold her. She really needs AT LEAST twin 250's. But, I suspect twin 300's would make that hull come alive. A pair of 150's? That is a horrible idea: She COULD get on plane... in the river, with a tailwind, going downstream.... but in the ocean? No way would I want that little power pushing me. Plus, you'd have the RPM's pegged at 5500 all day everyday.... early engine fatigue. MAYBE a single 350 duo prop, but I would want to see someone else do it 1st so I could have real world numbers.
Now, a pair of Suzuki 300's? NOW youre talking....!