How big until switch from I/O to Inboard

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Golfman25

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So been looking at boats in the 30-35 foot range. Many have twin v-drive inboards. Also many have twin Bravo 3 I/O. Do you think I/O can work at 35 feet? Or is the boat too big/heavy and puts a lot of stress on the outdrive? What size would you drop the I/O configuration?
 
Just went from a 33 donzi cruise with i/o's to a 38 hatteras. Maneuverability night and day with inboards
 
Our Regal is a 32 footer with twin Bravo 3's. I find it plenty maneuverable. I've no experience with inboards and indeed they may be superior, but my experience with the 3260 Cpmmodore is that the I/O is fine. I also believe that many feel this combo is more efficient than the inboard route.
 
I/O's are generally okay to 35 feet for planing boats like SeaRay and Regal etc. I had a 35' Regal with inboards and liked the maneuverability. The I/O will be quicker to plane and will get better fuel consumption. After 35+ feet, diesel is the only way to go if you want affordability and resale.
 
It has more to do with displacement or type of boat rather than just the length. You'll see performance boats over 40 feet... even 50 feet (Nor-Tech 50) that have I/Os, ... but you'll see inboard diesels on a 28 foot Bertram.
 
The decision of I/O vs inboard is made during the hull design stage. I/O ( and outboards ) are suited to certain types, often full planing, hulls. Inboards are better suited to semi-displacement and full displacement.

But the decision was made before the designer put pencil to paper ( or, rather, cursor to Autocad ).
 
Go I/O if you get axius on a newer boat.
Joystick docking is great.
Over 40' go pods if available.
 
Golfman it depends on what kind of baot you want. If it's a go fast boat I/O,you are getting a center console outboard, Cruising go with inboard.
 
Ferretti says you can go quite large with Arneson surface piercing drives. The ASD-16 drive has some impressive specs.
 
Formula does I/O diesels (Volvo) on their 37PC . . . 32kt cruise and better economy than my Cruisers 3372 at 25kts!!!
 
If you cant lift the drives out of the water the boat is too big for them.
 
As soon as you go from freshwater boating to saltwater boating. Size does not matter. Trailer boats don't count.
 
Sea Rays 450 Sundancer comes STANDARD with I/O's...not that I would get it...I think maneuverability would be horrible
 
quote:
Originally posted by RamSport47

Sea Rays 450 Sundancer comes STANDARD with I/O's...not that I would get it...I think maneuverability would be horrible

Click to expand...


Don't know what you mean, Kenny - Directional thrust (e.g., I/O's) is far more efficient than deflected thrust (I/B's) . . . kinda why cruise ships when to pods.
 
Actually I thought it was the drag from the shafts, skegs and all that what-not that is in between the hull and prop that made inboards less efficient than I/Os. Pods certainly make the boat more maneuverable as well.
 
quote:
Originally posted by Good Grief

quote:
Originally posted by RamSport47

Sea Rays 450 Sundancer comes STANDARD with I/O's...not that I would get it...I think maneuverability would be horrible

Click to expand...


Don't know what you mean, Kenny - Directional thrust (e.g., I/O's) is far more efficient than deflected thrust (I/B's) . . . kinda why cruise ships when to pods.

Click to expand...
Not quite making the connection between pods and I/Os. While they are both directional, the similarity ends there.

We have discussed many times over the benefits of inboards in close quarter maneuvers. Having outdrives hanging behind the boat provides a less desirable pivot point than props and rudders tucked up underneath. Even without the props turning, you still have directional control with the water moving past the rudders.
Lastly, the pods are tucked up under in a placement more akin to props/rudders than I/O.

Right?

Paul
 
Depends on the pod. Zeus your looking at props more in line with inboard. IPS had the props more mid-ship.

I hear IPS maneuvers way better than Zeus. Also more economical, but more vulnerable with forward facing props. Plus deeper draft!

I have owned 3 different propulsion systems out there. Bravo3, inboard and IPS.
My 34' with twin Bravo's was very manueverable as was my inboard.
Both were taken by wind and current and needed a careful Captain to understand and control.
IPS is un-comparable. I dock my current boat within inches, not feet.
Once you get used to a joystick and understand the amount of thrust and direction, docking is as simple as it gets. The biggest issue I have is sometimes making sure the joystick understands my direction because there is not much difference between some angles on the stick, so if i hit it to go reverse angle to port, i may be hitting it to go sideways to port and when docking this can be a big mistake!
 
The classic inboard puts the engine weight midships while I/O, V drive and PODs move it aft. Interior space is better with rear engines but handling and wind resistance are better with weight forward.

old fashioned it may be but there is real satisfaction making inboards dance that would be lacking in pods. But like stick shift cars pods are the future.

I probably wont want self driving cars either. :D
 
Personally, I like my straight inboards. But the admiral want's the space rear engines provide. So I am looking 30 to 35 feet. I am seeing 35 footers with I/O (BIII). They seem really "small" for that size boat. I am hesitant to consider for that size boat.
 
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