In fact, the boat with the IMCO splitter won race(s) last Sunday running a Paul Pfaff (PSI) blown motor of more than 1000 hp, and two IMCO extremes. This is the same boat shown at the LA Boat Show, the splitter was shown in the IMCO booth...

Diesel high performance boats? Maybe with gas turbines but other than that, none approach the power to weight ratios of gasoline engines.

As far as diesel powered boats and relatively good performance, it really all depends on the specific application. How fast, how often between overhauls, how much weight and how much money in the budget.

Change any of these variables and the end result could be any of the drives and engines written in this thread.

When it comes to diesels in the 700 ft.lb range and less, yanmar leads the industry with two engines that have been in service worldwide for at least three years.

Look at what is currently offered at the weight (895 pounds) of the 6LP at 315 hp, nothing else.

Look at what is offered at the weight of the 6LY ( 1186 pounds) at 440hp: nothing

volvo: the only engine close to this weight ,D6, offers 310 hp maximum and is just starting to be available.

cummins: 200 additional pounds gives you
380 hp maximum and just starting to be available


steyr-nothing
cat-nothing
GM-nothing
Peninsular-nothing
Iveco-nothing
perkins-nothing
john deere-nothing

Performance minded diesels are few and far between, primarily because diesel manufacturers are conservative and cannot imagine producing an engine which has a lifecycle similar to a high performance gas engine.

Over the past decade these engine OEM's have started to produce higher rpm and horsepower and shorter life powerplants.

With the new generation electronics, the sky is the limit. The yanmar 6LY can and will be produced with a higher output level within a year. Perhaps it is 500 hp and the life of the engine is 3000 hours, maybe in the future it is 600 hp and the life is 1000 hours.

The diesel market is slowly moving in the direction of performance. As fuel prices continue to climb, we americans, like the europeans will demand diesels.

The swedish GM marinized and supercharged diesel is the old GM 6.5 (now AM General block.) In the mid nineties, the GM/Isuzu designed diesel was marinized in isolated applications. Since the introduction in the GM pickups, there have been none allocated for other usage at any kind of volume.

Furthermore, what drive manufacturer has experience (working applications) with all of the engine manufacturers mentioned here?

Konrad Stern Drives- more diesel stern drive experience than any other drive manufacturer in the world.

FSPROP, quite true but I have to disagree that diesel manufacturers are conservative. Given the rate of progress of their engines, they are less conservative than gas motor manufacturers who are stuck with some very old technology. They just happen to be very large and serious firms who could make a very high-performance diesel to compete right up there with gas engines but they are way too serious about their products and service to produce something that would require an overhaul at 50 hours and would probably detonate if this was not done. Their marine business is usually a small part of their overall turnover and they cannot afford to get involved in something like this, due to the image they're trying to convey and due to their business & product philosophy.

However, there are still plenty of diesels which are competitive in terms of specific output. Many diesels produce more hp/liter of displacement than an HP525. Seatek, Yanmar, CRM, and even MTU do that but only Yanmar and to a lesser extent Seatek is doing so in the power range which is of interest to us. This is because diesels are used to power heavy stuff and thus the best examples of diesel technology are found in the 1000 to 3500hp power output range. A 2000-series V12 MTU is a very good engine, producing up to 2000hp. They are used to power stuff like Magnums and when you get one of those up to 70 mph, it's pretty impressive. Making them lighter is very feasible but at the expense of reliability which is a no-no with those enterprizes. Why? Once again, a guy with a Magnum who wants a lighter engine represents 0.1% of their customers while a guy with a large motoryacht who couldn't care less about weight and just wants it bulletproof represents 99.9% of their customers. Which type would get your preference if you were someone like MTU?

But I agree with FSPROPELLER as far as Yanmars and ECM is concerned, and I personally had Yanmars turned up to 550hp without any undesirable side-effects. However, we must understand that we need to be patient for this diesel technology to trickle down to smaller engines as the real diesel progress is happening above our heads, on bigger engines. In other words, while an engine of approx. 500 to 800hp will be the bread and butter of a gas manufacturer, a diesel manufacturer will do most of their business closer to 1500hp.

Performance is a very marginal market for diesel manufacturers and this is why not many are putting their best effort into it. Let's hope that what Yanmar is doing is a wake-up call for all of them, that Yanmar's effort and success shows others that our market is worth the investment...

C-spray,
We have looked at devices like that bur they need to be active. Once you break away the driver hardly ever notices or cares until it stops dissipating energy and dies. The concept is similar to a limited slip diff, they are limited and they slip. Good thought though.
We are looking at up to 1600 fl/lbs for on the WMD.
The weight and size of a 1000hp motor is more of a problem on your sport boat it is turning into a cruiser.
Smaller light weight diesels are comming and it will have a big impact on the sport boat community. We are looking forward to it.
pat W

FSPROPELLER: That's a hell of a first post. Where you be from mon?

Pat:

How much torque can the WSD handle ?? Can it handle the 440 Yanmar ??

Dr. Santiago,
Are you going racing this year?
WSD was built as a racing surface drive. It runs a smaller universal joint than the WMD. In racing it was taking 850 plus hp gas with a 1.80 gear ratio That is over 1300 ft lbs at the prop but that is relatively high shaft speed/ heavy impulse load. (racing)I have not run one with diesel yet. We have a boat in Europe going together. I will let you know how it turns out. It is a raceboat not pleasure and has a similar motor to the Yanmar going in it.
The Yanmar is a good "high speed" light diesel. It is like the seatek in many ways just smaller. Have they gone to common rail yet? Do they have any new motors comming?
We had good success in Europe in Class 1 and 2 with Seatek and the multispeeds. It is a shame that they have out-lawed diesels In Europe and here. It makes developement slow down but not stop.
pat W

Super T:

I agree with you, there is no question that the diesel evolution has progressed significantly over the past decade. People think of the 5.7 litre diesel from GM and in my opinion that engine really hurt the diesel market in the US. The Standyne rotary fuel pump was a huge mistake. People in the states say " why do I want one of those smokey dirty engines?"

Today, with electronic fuel management systems and better fuel presentation, the engine power curve can be designed for the application. It can even change based on the data it receives while in operation. No more smoke or unburnt fuel and power where you need it without the parasitic loss of the supercharger. There is always enough air, because there is never too much fuel.

As you described the view from the diesel OEM, It is not worth it for them to build something that doesn't stand up because all of the demand is for durability.

Still, the diesel fuel source is more efficient and eventually, as the demand changes, the engines will meet the demand. Carry the same weight in fuel and have a range that is 50-70 % greater.

Yanmar and anyone that wishes to stay in the market will go to some type of electronic fuel management. The EPA has mandated it. For the engine guys it is a huge investment, for everyone else it means a new era of engines.

(Sounding like a broken record..) The new D4/D6 Volvos already have all of these engine management features. The ECM also compensates for fuel temperature/viscosity, the entire engine/drive is fly-by-wire (throttle and shift), and has it's own CAN network for displays/trouble-shooting.

Volvo quote:
The capacity to control the flow of fuel to every cylinder at every moment is completely critical for the engine’s performance and environmental properties. The first stage is to replace mechanical control with electronic, a concept that Volvo Penta introduced in 1995 with its EDC-system.

The next major step is being taken now with the introduction of electronically controlled, common rail direct injection.

“In simplified terms, common rail means the fuel is constantly under pressure, which creates a continuous injection pressure in the system. The injectors in every cylinder are controlled by electronics that can release the right amount of fuel at precisely the right time. With electronically controlled common rail, we can now control fuel combustion in a way that was never possible in the past. The result is improved fuel consumption with low exhaust emissions that will meet future comprehensive requirements planned for introduction in Europe and the US in 2006,” says Rickard Stefansson and continues.

“The fuel is fed into the cylinders as many as three times per power stroke. This provides a softer combustion and much lower noise level – the characteristic diesel knock is completely gone. The D4 and D6 engines can also be driven on environmental diesel with full performance standards. And they do not lose power if the fuel is warm, since the fuel system adjusts and compensates for temperature differences.

The D4 and D6 are also equipped with EVC, Volvo Penta’s new electronic CAN-bus based platform, which enables the engine, control and instruments – as well as other functions on the boat – to communicate and exchange information.

The fuel is introduced under extremely high pressure, which has a couple of advantages. One if much finer atomization, but the other is even neater: because of the higher pressure, the fuel obviously flows faster. The allows the fuel to be introduced at exactly the right time during the compression/power strokes, not just once but several times per cycle. Now, instead of dumping in all the fuel at once and generating the classic diesel knock, the fuel can be fed in at several points per cycle, giving smoother, cleaner, and more powerful combustion. Pretty cool. I would suppose that lessening the shock on the internal components should also lead to better hp/weight ratios.

As SuperT has pointed out, only time will tell whether or not these packages are appropriate for sport boats. The 350 hp package slated for test this summer is intended for a 50-mph sport cruiser.

Pat:
I am done with racing for now.
Can you explain the diference between the WSD and the WMD? To me the WSD "looks' like is stronger. And what would be the advantage of the WMD v.s. the Anerson ASD8 hook to a Yanmar 440 ?