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Diesel Performance ???
I've been pondering this all day, why don't diesels run as fast as gas engines in boats. It seems to me that with the tremendous torque of a diesel and the proper gearing and prop selection, they should perform as well as a gas job.
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Glad you brought that up!!! I have been pondering this for some time too. I think they would be a much better powerplant. Ton of torque, and easy to increase power. With only a computer chip my F-350 has around 400 hp and 500+ lbs of torque. Do the injectors, larger turbo and exhaust and forget it!! There was a comparison done in Powerboat mag back in the summer between 2 Fountains, 1 with gas, the other with diesels and Arnesons. The diesel was equal, except $100,000.00 more!!!!! Plus it does not need a rebuild for 10,000 hrs.
My brother-in-law was going to repower a 1988 30' Checkmate with deisels. He said the deisel only weighs 160 lbs more than a big block. I would love to hear more about deisels. |
One problem is that they weigh alot. That alone will slow the diesel down. Another problem is that they have a very narrow power band. Most top out at 3k, many sooner. What that means is that a steeper prop is needed for speed which results in a very soggy bottom end. This is accentented by the use of turbos which won't spool up until the engine sees some r's. The cruiser guys like them because they don't care about the weight, and they like the TBO times. Besides, not many cruiser guys even know what a hole shot is.
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I have bravo ones, whats a hole shot?
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power to weight ratio.
In a 9000 pound boat, you add 1300 pounds for a diesel swap to 350 hp Caterpillars. You also can't use Bravos with them. In an 18000 pound cruiser you add 1300 pounds for a diesel swap. You got v-drives or straight inboards and drivetrain durability is not a problem. My Sea Ray was available with 330hp Mercruiser V-drive 454's that topped out at 34 mph (4500rpm), cruised at 22mph (3200rpm). Used 50gph WOT (both motors) and 29GPH cruise. I got 310 horse Cats. Tops out at 37mph (2800rpm), cruises at 30mph (2400rpm). Uses 34GPH WOT, and 24GPH cruise. Runs just as hard with 15 people and full tanks as it does empty. Planes effortlessly (after turbo spool up), and never sounds like it is laboring. Had to experience it myself before checking the option box for the upgrade - it was expensive. I'll never run gas motors in a big boat again. Performance boat? Hard to overcome the power to weight ratio issue (unless you use questionable aluminum block Yanmars). The turbo lag is a real issue as well, but only coming out of the hole... Other items: Diesel will not explode due to buildup of fumes... Diesel will not silently kill you from Carbon Monoxide poisoning - yes it still puts out some CO, but you will wake up vomiting from the other comonents in the exhaust long before you will succumb to CO poisoning... Diesel fuel is usually cheaper than gasoline. Diesels sound cool. Bad? soot. gets everywhere, even on "sootless" new tech engines... The Fountain with Yanmars and Arnesons? I think it is the coolest... |
Ken, I know what you mean about the truck. I've got a 3500 Dodge with 370 horse marine injectors, "hot" fueling plate, 4'' exhaust.ect.....will run 16.2 in the 1/4 at 7900#. This is what lead me to start thinking about the diesel thing.
If I remember correctly didn't Fountain set a speed record with twin Diesel power? |
I would love to see a 24HTM or 25-26Daytona with the MC 300hp diesel and bravo one package.
30" prop, 1.12 drive, 3500rpm = 88MPH less slip = 80MPH! |
I know a guy with a 2002 Fountain 38 Sport Cruiser with Yenmar's and surface drives. Don't hold me to it, but I believe the engines are rated at around 415HP each.
Bottom line is this is a VERY HEAVY boat and he is running 68 MPH on GPS. Not too bad when you consider all things. I have also seen a 50 Foot Nortech with Diesels and if I remember right they are running over 80 MPH. In my opinion we will start to see more diesels in performance boats in the years to come. Just wish they could make them sound a little better. LOL:D |
Sonic 30SS, My truck runs 16.3!!!
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There are several new diesel packages available for offshore boats. Tremendous weight savings over earlier diesel options plus a much wider power band. And they come with outdrives. Merc is even offering one.
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yanmar is very popular in europe for the moment...
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Ken what does it weigh????
I feel a Ford /Dodge thing coming on!!LOL:D |
OOPS Dock Holiday(love the name)
What do you mean sound better ? ya ever heard a Cummins with straight exhaust @ 40# of boost blow by???? I can only imagine what two would sound like on the water!!:D |
Ken,
OK ,now we know your 60' time...how about the 1/4:D :D :D:o |
I think mine is in the neightborhood of 6500 lbs, but not sure.
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Originally posted by Sonic30ss OOPS Dock Holiday(love the name) What do you mean sound better ? ya ever heard a Cummins with straight exhaust @ 40# of boost blow by???? I can only imagine what two would sound like on the water!!:D I just heard a Ford F-250 PS with the ATS dual exhaust system and it also sounds like a gas engine at idle. |
Ken, that about right for a 250
Mopower, LOL . Can't quite figure out the screen name, is that MOPar or I need more power? |
Diesels
Hi!
Phantom Powerboats deliver their Phantom 34 Classic with twin Yanmar 315 hp engines and Bravo One lowerunits. Prive approx. 150K USD. Top speed is 70 mph. Crusing all day is 65 mph. And fuelconsumption, read 15 gallons per hour at cruising. Longvity = more than 10.000 hours. A V8 has to be rebuilt every second hundred hours...and use 40 gallons at 4.000 rpms.... In Norway we pay 4 USD per Gallon for gas, 2 USD per Gallon diesel.... Phantom 34 can be delivered with twin Yanmars 415 and B Max drive for USD 200K upon request. Top speed in excess of 80 mph. Tweak the engines a little, and you will run close to 90 mph. THis is all according to Will Smith. Cruise at 75-80 mph all day long.... I am myself digging after money to buy this package. Add 29% in Value Added Tax, and then you understand why I have to dig hard and long! Meanwhile it will be a UK Phantom 25 & Promax 300 for cruise + a Skater 28 with twin 2.5 Offshore Race engines for fast fun. Cheers, Toffen G |
Toffen,
Thats what I'm talkin' about!!!!!!!!!!! Do they have a web site? |
Phantom and diesel
Hi!
Check out www.phantomboats.com or call Will Smith at 941-351-3760. Their boats are awesome and fast! Cheers, Toffen G |
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