Seasport 22 inboard to out board

[Alex_c]

Following the hull is fine just a different design but essentially a hull extension

Are there different considerations for hull centre of gravity when adding a hull extension vs a tapered pod? I would assume they apply different propulsion and drag forces to the hull and would need to be accounted for? How does outboard weight, power and pod length factor in to that?

 

[salmonkiller01]

Are there different considerations for hull centre of gravity when adding a hull extension vs a tapered pod? I would assume they apply different propulsion and drag forces to the hull and would need to be accounted for? How does outboard weight, power and pod length factor in to that?

Think you’re over thinking it. Hull extension is more drag than stepped on plane. (Less hull in water, less drag.
Generally brackets or Pods are 28-34” set backs. Depending on what someone wants or need for engine tilt. Too long they look goofy after 36”

Centre of gravity not sure how that comes in.

Engine power is what one wants or needs.

Flotation at rest and trolling is tricky and is a best guess sometimes. Generally I use 25-35% of engine weight on the bracket, under water.
1000 pounds 350 pound flotation.
Too much not good too little your moving weight forward

 

[Alex_c]

Makes sense, I assumed a hull extension would have more drag, so wondered how that would affect set-back from transom vs a pod. I hear a lot of stories of podded boats riding like butt or porpoising, so wondering what design elements ppl usually *don’t* overthink that lead to sub-optimal performance.

 

[salmonkiller01]

Makes sense, I assumed a hull extension would have more drag, so wondered how that would affect set-back from transom vs a pod. I hear a lot of stories of podded boats riding like butt or porpoising, so wondering what design elements ppl usually *don’t* overthink that lead to sub-optimal performance.

From my experience porpoising can be cured adjusting engine height on the stepped/raked brackets.
Take it to a reputable guy. I am using E&D and they are great. Built hundreds of them over the years

 

[Alex_c]

Nice. My theoretical pod project boat shouldn’t porpoise then, theoretically.

 

[ship happens]

Just ditch those tab actuators and put in some bolts or a pair of lencos. Way better and would clean things up. My 2c.

All planing boats will porpoise if trimmed improperly etc. That's what trim tabs are for

 

[salmonkiller01]

Just ditch those tab actuators and put in some bolts or a pair of lencos. Way better and would clean things up. My 2c.

All planing boats will porpoise if trimmed improperly etc. That's what trim tabs are for

I have been looking at the Bennett bolt tabs. Break out another $1000. lol. Most likely stick with what I have. Not worried about seeing the hoses. Two motors should hide them.
2 new raymarine screens, radar, auto pilot, couple steering cylinders. It is starting to add up and power not on. lol

 

[SpringVelocity]

I will be interested how this works on my next build with that rake angle. Not sure on advantage but maybe larger boats need it.

My boats obviously way smaller and doesn't rake like that. I was lucky with mine it didn't purpose at all.

Looks good.

 

[ship happens]

I have been looking at the Bennett bolt tabs. Break out another $1000. lol. Most likely stick with what I have. Not worried about seeing the hoses. Two motors should hide them.
2 new raymarine screens, radar, auto pilot, couple steering cylinders. It is starting to add up and power not on. lol

I have a set of actuators with the wiring I'd sell for cost. Would need a switch but any switch will work really.

I've repaired those boat leveler systems a few times and the external hose idea was absolutely the wrong idea. Everything about them to me is micky mouse.

 

[salmonkiller01]

I have a set of actuators with the wiring I'd sell for cost. Would need a switch but any switch will work really.

I've repaired those boat leveler systems a few times and the external hose idea was absolutely the wrong idea. Everything about them to me is micky mouse.

Not really the cost, it is drilling holes
In transom then running wires from fish boxes, thru stringers….. just turns into a lot of work for some cosmetic gain. Yes the are faster.
As for Mickey Mouse, they have lasted 20 years so I am sure they will last longer. Had more issues with Bennett pumps than the boat levelers.
Going to spend more $$$ on steering and autopilot hoses, valves… and then the whole raymarine integrated into the mercury’s. That was a stupid expensive mercury part to link.

 

[ship happens]

Not really the cost, it is drilling holes
In transom then running wires from fish boxes, thru stringers….. just turns into a lot of work for some cosmetic gain. Yes the are faster.
As for Mickey Mouse, they have lasted 20 years so I am sure they will last longer. Had more issues with Bennett pumps than the boat levelers.
Going to spend more $$$ on steering and autopilot hoses, valves… and then the whole raymarine integrated into the mercury’s. That was a stupid expensive mercury part to link.

Yeah that makes it tough to install but it sure is worth it in the end.

 

[Brando]

Did they put any stringers or bracing inside the pod? Moving along quickly

 

[salmonkiller01]

Did they put any stringers or bracing inside the pod? Moving along quickly

Yes they did

 

[mitch184]

On the pod.. extension vs stepped. Stepped won't always be more efficient than a bottom extension. On real heavy boats with narrow beams or short waterline lengths, they suffer from real heavy bottom loading. In this case, adding wetted surface area often reduces overall resistance and increases efficiency due to reducing wave making resistance.

It's really case by case.

 

[Rain City]

On the pod.. extension vs stepped. Stepped won't always be more efficient than a bottom extension. On real heavy boats with narrow beams or short waterline lengths, they suffer from real heavy bottom loading. In this case, adding wetted surface area often reduces overall resistance and increases efficiency due to reducing wave making resistance.

It's really case by case.

This is something I learned more recently. Length to weight plays a big factor in efficiency. So adding hull, even on a big heavy boat, can actually make you more efficient. Not that I understood why. I always figured more hull in the water meant more drag.

 

[salmonkiller01]

On the pod.. extension vs stepped. Stepped won't always be more efficient than a bottom extension. On real heavy boats with narrow beams or short waterline lengths, they suffer from real heavy bottom loading. In this case, adding wetted surface area often reduces overall resistance and increases efficiency due to reducing wave making resistance.

It's really case by case.

I can’t afford the big heavy boats anyways. lol Lots of factors.
On a smaller boat hull extension is better also as you make an 18 into a 21. Lots of factors. I went with what worked for me on my Grady and hourston. Seasport from the factory have stepped

 

[mitch184]

A lot of boat manufacturers run stepped brackets because they are easier to install and the same bracket will work for multiple boats. They are FAR from optimized.

 

[salmonkiller01]

A lot of boat manufacturers run stepped brackets because they are easier to install and the same bracket will work for multiple boats. They are FAR from optimized

Engines higher out of the water on the stepped brackets.

 

[mitch184]

Engines higher out of the water on the stepped brackets.

Yep. Not always a good thing but can be an advantage on some boats

 

[wolf]

Engines higher out of the water on the stepped brackets.

not always. all depends on if its a normal Xl or XXL From What I learned about stepped and non stepped, I know on stepped designs you need alot more power to get up on plane and hold there. hence full extension is better, on some boats especially heavy boats from what ive learned. I asked my builder and right away he said NO NO NO and explained it all to me. I trust a guy who has built pods for 30 years and from the referals .
My buddy had a 23 hourston done by a company I wont say. stepped he needed to do 4500 just to cruise if he brought it back the butt end would fall off and lose his plane. SO off went that pod and went with a hull extension and was 100 % better.
I persoanlly went with the XXL as i wanted more engine out of water and I ahte when I see pods under water while trolling. to me defeats the purpose..