Mercury V12 600hp Verado Outboard Engine

But these engines aren't efficient! ????

Don't start that "petrol is as efficient as diesel" nonsense agin - it isn't, it never ever will be.

Its quieter, smoother and more powerful weight for weight, but it is never going to be as efficient as diesel. And availability is rubbish in UK marinas.

What does a 450hp diesel inboard burn and compare that to a 450hp outboard, I bet the outboard is burning a good 25-50% more litres per hour
Bet it doesn’t you’re taking rubbish I’m afraid.
apart from that. I never brought up the petrol being more efficient than a diesel again. You did. Just there.
I mentioned only that mercury should be applauded for making efficient engines as they do now. Speaking from experience here.Can you say the same ? I’ve a V8 mpi petrol, that’s every bit as efficient as the same Hp diesel equivalent. Costs so much less to buy, run and service. Tried and tested.
I also have a new mercury 115 CT outboard. That can achieve nearly 2 miles per litre of fuel at 25 mph cruising. A rival for any diesel that could do the same. I doubt there is a diesel rival for that though. That could see 45 mph flat out. There just likely isn’t a diesel that could do that.
So there it is, in black and white and real world examples. Get with the times fella. All the best.
 
But these engines aren't efficient! ????

Don't start that "petrol is as efficient as diesel" nonsense agin - it isn't, it never ever will be.

Its quieter, smoother and more powerful weight for weight, but it is never going to be as efficient as diesel. And availability is rubbish in UK marinas.

What does a 450hp diesel inboard burn and compare that to a 450hp outboard, I bet the outboard is burning a good 25-50% more litres per hour
You should have read what I actually said in the previous post, before throwing crap like this about. Get a hold of yourself man. Go and have a read. Then educate yourself on modern mercury outboards and their manufacturing process and casting process. It’s a wonder what they are managing now. Time better spent for you, rather than made up junk like the above.
 
my take is as technologically interesting as it is, the v12 outboard is an answer to a question no one asked. Except in Miami
You’ll be aware of makers like fairline going to outboards just recently, for their new boat ? Many will follow. We are a little behind here, I’d think.
 
that’s a good one. I think I’ve spilled my coffee ?
Are you suggesting a Tamd61a straight 6 monster at 306hp, is more fuel efficient than my petrol MPi ? I know it isn’t. Same power, give or take. Apart from that. I know what both cost to service too. There is an enormous difference. Never mind the weight. I don’t think there is a diesel, even from the same time as my MPi in 2003, with the same power, that will be better on fuel. Period. Educate yourself over another coffee !
 
You’ll be aware of makers like fairline going to outboards just recently, for their new boat ? Many will follow. We are a little behind here, I’d think.
Wish guys would learn a little more, before being so ignorant and posting stuff like this. Such a shame. Go look up modern mercury engines. You’ll love it. This isn’t the 70’s and 80’s anymore.
 
Cummins 8.3 600hp about 110lph full noise. The new Mercury outboard will be 200 plus. She’d load more torque with the diesel too. Fine if you are American with a show off set of triples or quads on your day boat. I can see troll tendencies so I’ve made my point and I’ll leave it at that
 
Cummins 8.3 600hp about 110lph full noise. The new Mercury outboard will be 200 plus. She’d load more torque with the diesel too. Fine if you are American with a show off set of triples or quads on your day boat. I can see troll tendencies so I’ve made my point and I’ll leave it at that
You sure have. Not sure where those figures came from.
 
It’s a heavy bugger! 570kg.
Almost the weight of 2 x 450s.
Spot on.
I guess there must be a selling point for these beasts, because it's not like at Mercury they don't know their business.
But I struggle to see what it is, because power alone ain't the real name of the game - power to weight ratio is.
And at 1.05 hp/kg, this thing is nowhere near the 1.32 of their own existing Verado 400 - let alone the 1.44 of the 450R.
BTW, all of them are just laughable in comparison with the venerable 2 stroke 2.5 EFI, whose stock power to weight was around 1.7, and used to be easily tuned to go well above 2, reaching ear-bleeding RPM level in the process.
Now, THAT was a thrilling powerplant, for boats designed to reach properly scary speeds.

Then again, as Whippersnapper correctly pointed out, pretty sure there must be a decent market of Miami drug dealers, for which the show-off factor is crucial. And it's undeniable that a big boat with four of these things hanging at the stern is bound to raise some eyebrows.

What I really don't get is the debate on fuel efficiency, which is only relevant for Mercury Marketing dept., because these days some brochure claims about that are as necessary for selling engines as pics of sunbathing babes in bikini are for selling boats.
But in real life, it's blatantly obvious that neither boatbuilders nor their drug dealer clients would care one iota about that.
 
Wish guys would learn a little more, before being so ignorant and posting stuff like this. Such a shame. Go look up modern mercury engines. You’ll love it. This isn’t the 70’s and 80’s anymore.

Just looked up a couple of boat tests of very similar style boats, one had twin 300hp Mercury outboards, the other twin sterndrive diesel of similar HP. At full throttle the outboards were using 227lph, the inboards 96lph. The outboards were making 35.2 knots, the diesel inboards 35.6 knots. These are boats with current generation engines.
 
Just looked up a couple of boat tests of very similar style boats, one had twin 300hp Mercury outboards, the other twin sterndrive diesel of similar HP. At full throttle the outboards were using 227lph, the inboards 96lph. The outboards were making 35.2 knots, the diesel inboards 35.6 knots. These are boats with current generation engines.

Perfectly correct.

Qbhoy, it doesn’t matter how loud or often you shout it - a petrol engine I will never be more than 60-70% as efficient as a diesel, unless you have an alternative definition of efficient to everyone else??

A 600hp out board will burn about (give or take) 200-250 litres per hour - the same power output diesel will burn 120-140 litres per hour ish - FACT.

PLEASE show us the fuel burn from any petrol engine that IS AS EFFICIENT as the same power output diesel OF THE SAME AGE!

Please, because many would love to buy these mythical engines!

Why do you think nobody makes 70’ boats with petrols? (The specialist offshore racers excepted) - because diesel is what you need to drive a large heavy boat.

Outboards are brilliant things, perfect up to 20-30ft or so, but after that they just become way too thirsty.



But the floor is yours. Please give us two engines, the same age, same horsepower, where the petrol version can get within 10% of the efficiency and fuel burn at wot and I will concede the point - but you can’t because there isn’t one....
 
Just looked up a couple of boat tests of very similar style boats, one had twin 300hp Mercury outboards, the other twin sterndrive diesel of similar HP. At full throttle the outboards were using 227lph, the inboards 96lph. The outboards were making 35.2 knots, the diesel inboards 35.6 knots. These are boats with current generation engines.
You’re going to have to read my post again, I think.
 
Perfectly correct.

Qbhoy, it doesn’t matter how loud or often you shout it - a petrol engine I will never be more than 60-70% as efficient as a diesel, unless you have an alternative definition of efficient to everyone else??

A 600hp out board will burn about (give or take) 200-250 litres per hour - the same power output diesel will burn 120-140 litres per hour ish - FACT.

PLEASE show us the fuel burn from any petrol engine that IS AS EFFICIENT as the same power output diesel OF THE SAME AGE!

Please, because many would love to buy these mythical engines!

Why do you think nobody makes 70’ boats with petrols? (The specialist offshore racers excepted) - because diesel is what you need to drive a large heavy boat.

Outboards are brilliant things, perfect up to 20-30ft or so, but after that they just become way too thirsty.



But the floor is yours. Please give us two engines, the same age, same horsepower, where the petrol version can get within 10% of the efficiency and fuel burn at wot and I will concede the point - but you can’t because there isn’t one....
Again. Please see my earlier post. All the best.
 
Again. Please see my earlier post. All the best.
So this is my mpi cruising rpm at about 24/25mph. It’s will be burning about 14/15 litres per hour at this I’m sure. Find me a diesel from 2003 that will do that comparably with 300 ish hp. It will go on to around 67 mph at 5100 rpm. Show me a diesel that will do this ? There isn’t one. Full stop There is a fact for you. Ecu actual real life detail for you. The floor is yours my man.
 

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I’m no expert but I think you’re comparing apples and oranges as engines are about application.

you put a 2003 mpi in a sports boat......great mpg. Put a tamd61 in the same boat......won’t fit for a start and probably wouldn’t even plane.

swap boats to a Fairline sedan 36.....and the petrol mpi won’t even get it on the plane. All about torque I guess so it’s not a fair comparison. That’s why these 70ft sport fishers need 5 or 6 outboards? Perhaps the v12 will reduce that to 3 or 4 so make good man maths sense ???
 
So this is my mpi cruising rpm at about 24/25mph. It’s will be burning about 14/15 litres per hour at this I’m sure. Find me a diesel from 2003 that will do that comparably with 300 ish hp. It will go on to around 67 mph at 5100 rpm. Show me a diesel that will do this ? There isn’t one. Full stop There is a fact for you. Ecu actual real life detail for you. The floor is yours my man.

I think you are deluded with the figures you are quoting above , but tell me the exact boat and engine combo and i'll happily admit if I am wrong.


Edit

From your own post below, your fuel consumption is more like 25 to 28 lph, if your figures are correct. Up to double what you quote above. In the boat in question diesel would simply be the wrong choice, but however you look at it, diesel gives you more MPG than Petrol, often by a considerable margin as I demonstrated in a previous post.


Love posts like this. Two of my boats and details listed below. Should be known that the below is taken from pin point accurate ecu given data to smart craft instruments and gps speeds.

Campion Chase performance edition
18ft stepped hull with pad
1380 kgs dry
300ish HP V8 MPi merc with cam and Corsa full system
Cruising speed 25-28mph @2200/2300 rpm
About 1 litre of fuel per mile at cruise
Similar consumption at about 1100/1200 rpm and 6mph
Full throttle, depending on what prop is on that day is around 63-67 mph gps, fuel consumption.....lots !
 
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I’m no expert but I think you’re comparing apples and oranges as engines are about application.
Spot on.

QBhoy, you don't need to convince anyone that modern outboards are good. They wouldn't sell as hot cakes if they weren't.
It's when you jumped in the conclusion that petrol engines are "more fuel efficient" than diesel engines, that you dug the hole in which you are now.
And from where, as the old saying goes, you'd better stop digging.

See, the point is that there's only one commonly accepted definition of fuel efficiency of internal combustion engines, and it's the Brake-Specific Fuel Consumption, aka "BSFC".
There are actually slight variations on that, because some engine manufacturers use the weight rather the volume of fuel, and you can either use kW or hp to measure power, but this is just hair splitting.
Essentially, it's meant to measure the amount of fuel that one engine burns for each unit of power produced.
And the crux of the matter is that there are physical reasons why even the worst diesel engines are, and will always be, more fuel efficient than the latest and greatest petrol engines.

Of course MPI, direct injection, and many other tricks all contributed to improve the fuel efficiency of petrol engines over the years - as well as others factors did with diesels, anyway.
But none of these factors, neither alone nor all together, can circumvent physics.

For this reason, if you take the following table, which is obviously generic and based on averages, and you compare it with the specs of ANY engine, you will be surprised to see how valid the approximation is.
Don't take my word for it, give it a try.
g4mVnqqC_o.jpg
 
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