54 motor yacht

[Boatsb]

More air inside.

Funny but true.

Displacement is displacement.

 

[SKYCHENEY]

More air inside.

Hot air?

 

[Freeebird]

You're just messing with us right?

I would NEVER do that.

 

[Freeebird]

OP, if it’s of any help, we just calculated our fuel mileage after topping the tanks in Carrabelle. 10 knots @ 1,300 which yielded 1MPG. 60MY with the same 8V92 720HP engines as yours. Not bad for a Hatt that’s heavier, longer and wider than your 54MY. It’s easy enough to look at numbers on the 53ED Boating Magazine test in the brochure archives on here with the smaller 8V71’s.

Now if you put yours in the wind like we did on a separate tank, I’m sure you’ll get better numbers than our 16 knots @ 2,000 which yielded about .35 MPG. We were just getting ahead of a cold front and let her eat.

 

[SKYCHENEY]

OP, if it’s of any help, we just calculated our fuel mileage after topping the tanks in Carrabelle. 10 knots @ 1,300 which yielded 1MPG. 60MY with the same 8V92 720HP engines as yours. Not bad for a Hatt that’s heavier, longer and wider than your 54MY. It’s easy enough to look at numbers on the 53ED Boating Magazine test in the brochure archives on here with the smaller 8V71’s.

Now if you put yours in the wind like we did on a separate tank, I’m sure you’ll get better numbers than our 16 knots @ 2,000 which yielded about .35 MPG. We were just getting ahead of a cold front and let her eat.

My 53ED with 6v92's @465hp and running 1300rpm yields 9.5kts and 10gph, so about the same.

 

[Captain Ralph]

* themselves

I don’t mind that you and Pascal have embarrassed yourselves. The idea that larger engines have no effect on fuel economy is absurd. Drop the same power in a 54MY and 53MY and fuel usage will be very close to the same at hull speed. That’s what we were talking about, wasn’t it?

I'm late back but my quote on you;

Bull... oney. 20 inches of beam means nothing. Ever see a hull speed calculation take beam into account?

Was about beam.

 

[Captain Ralph]

Now, if you want to discuss hp vs the same hull speed.
I have done this many times in re-power projects.

AT THE SAME WEIGHT; Producing the same HP from a single 500 hp engine (say 400 HP) consumes the same fuel as a 700 hp engine. HP takes the same amount of fuel. Simply 1/10 gallon of diesel per HP /2 for a turbo engine.
400 hp or 20 gph will move the same hull at the same speed if the engines weigh the same.

Yes, at the same HP, they both produce the same hull speed.
Since it takes the same hp to move a hull thru the water at the same speed. IF the higher HP engine weighs more, there may be more friction on the hull to the water. Pending hull design and speed desired.

Now the work; That same engine with higher HP may move the hull faster but will certainly consume more fuel.

My personal example; Replaced a 260hp with a 340 hp, did not change props. Same fuel burn per hull speed per same weight.
Then added more weight; divers, tanks, weights, equipment and food for off shore dive trips.
Lots more weight, lots more HP developed to maintain same boat speed. Yes, lower wet line and then,, more fuel required to maintain the same hull speed.


F I

 

[Captain Ralph]

The extra beam width makes the boat sit higher in the water and lessens the draft.

Before I ask you what this leads to I have to ask,, what are you smoking and do you have enough to share???

 

[Freeebird]

Before I ask you what this leads to I have to ask,, what are you smoking and do you have enough to share???

You’ll have to take off that tie first.

 

[Freeebird]

My 53ED with 6v92's @465hp and running 1300rpm yields 9.5kts and 10gph, so about the same.

Just to keep things straight, I’m using statue miles. We were burning about 12GPH and running the smaller generator.

It sure took a long time for my point to catch on, but I think we finally got there.

 

[Pascal]

Before I ask you what this leads to I have to ask,, what are you smoking and do you have enough to share???

Don’t waste your time Ralph... refer to post 35.. about the pigs.

 

[krush]

I could of slowed down a bit and asked the extra CID (torque) to help, but I fear that is beyond your visions or topic.

Torque is irrelevant and has almost zero purpose for being mentioned in boat/ships. Determining shaft size would be one of those few topics.

Just to keep things straight, I’m using statue miles....

There's your problem. Maybe you should use real units?!?

 

[Freeebird]

Don’t waste your time Ralph... refer to post 35.. about the pigs.

That was aimed at you, Porky.

 

[Freeebird]

There's your problem. Maybe you should use real units?!?

ICW and rivers are in statute miles. Besides, like 95% of the crap brought up on this thread, that has nothing to do with fuel burn at hull speed on a 54MY. I just didn’t want Sky to think we are getting the same numbers with a bigger, wider, heavier boat with bigger engines.

I still think we should talk about rocket science.

 

[Pascal]

That was aimed at you, Porky.

I guess the aim was off as you have demonstrated.

 

[Freeebird]

I'm sure they would be the same as a classic 53my. You can do a search on here and find some info.

The 54 has more beam and will burn more than the classic 53 at hull speed. About 12/13 GPH if i remember right.

I did a delivery with one years ago. Don’t remember the burn at fast cruise which was about 17/18kts

Isn’t this where things went sideways?

You’ve been proven wrong, so why not just let it go?

Even in this 60MY the fuel burn is 12GPH @ 10 knots, and that’s with running a generator. Maybe someone with a 54MY will chime in and post their numbers as they would have to be better. You weren’t comparing numbers with what you got with with your one engine 53 against the 54MY you delivered, were you?

 

[Pascal]

You claimed the fuel difference at hull speed between a 15’10 and the later wide beam boats was because of larger engines and not the extra beam. I posted fuel burn per hp for a number of Detroits showing the exact same numbers regardless of engine size and you still claim beam doesn’t affect fuel burn...

You know, for a self proclaimed red neck, you distord facts like a flaming liberal

 

[oscarvan]

You know, for a self proclaimed red neck, you distort facts like a flaming liberal

, .

 

[Boatsb]

Isn't fuel burn dependent on many variables. Like engine alignment, propeller efficiency, engine efficiency, total weight of the vessel, torque curve , V struts vs single. Rudder size,

The list goes on.


Hull speed is hull speed. And for some reason the argument seems to keep going when proven wrong.

I guess if you think you cant be wrong you keep pushing your opinions with or knowledge.

Mr engineer what say you?

 

[Freeebird]

You claimed the fuel difference at hull speed between a 15’10 and the later wide beam boats was because of larger engines and not the extra beam. I posted fuel burn per hp for a number of Detroits showing the exact same numbers regardless of engine size and you still claim beam doesn’t affect fuel burn...

You know, for a self proclaimed red neck, you distord facts like a flaming liberal

Uh, excuse me, Hillary, but redneck is one word, and I won’t even get into “distord”. I said IF the 54 got worse fuel mileage, it would be due to the larger/thirstier engines instead of a minimal difference in beam width. It’s all there for your re-reading pleasure.

Are you sure you’re not flying a Biden flag?

I have disproven your original claim BIGLY, so my win is UGE.

 

[davidwigler]

I promised myself I would stay out of this fray but I do have a question. What is the beam on the 54 and the 60MY? Aren’t they both about 18?