Duramax boat engines????
 

I remember seeing a while back a boat being rigged with Marine Duramax engines. It was yellow is about the only thing I remember.

What ever happened to this boat? did this work?? I actually thought gm was behind it.

The reason I ask is I just got a new duramax truck (my first diesel). And the torque is crazy. And you see guys getting 1200+HP out of these engines I would think it would be a good fit especially when you figure you can cool the exhaust with water.

I think Banks marinises duramaxes or they at least used to for work boats..

Yeah I searched the forum a little and found some stuff. I was more interested if someone had done a high HP version.

As said banks builds duramax motors to order, but cummins/merc offers a performance based 6.7l straight from merc.

Someone was building this (the old Tommy Bahama MTI) with a Duramax motor a while back but I never heard whatever came of it.

I built a 900hp duramax for my 2500, let's just say for a boat buy a Teague big blower motor, it will be cheaper! Pistons $3000, rods $3000, heads $5000, turbos $7500...... Etc etc adds up even faster than boat parts!

The guys at FASS fuel pumps told me that old Tommy Bahama MTI is running their pumps on the Duramaxes. That was the only marine diesel application they had done prior to mine. They didn't have any details though.

http://www.bankspower.com/galesinsid...Mighty-Duramax

wow

Impressive

Sweet!

Anyone know what the boat was that they tested these motors in?

And can someone explain how a twin turbo'd AND supercharged motor only puts out 700hp?? Explain how 700 HP in diesel format is different from 700hp in gas format please.

Duramax marine engines have been in production in Europe for years. Banks purchased the North American rights but never brought a production model to market. The "MarineDiesel" Duramax's have been available here for a little over a year now. They've got several models and HP ratings. The VGT gives it excellent hole shot and fuel economy. It's a very nice, relatively lightweight package that takes up about as much space as a 496, and has proven itself in commercial and military applications all over the world.

http://www.marinedieselengineering.com/md/engines/tsc/

Aside from the TSC don't know why you would want any of these over a Yanmar. A lot more bulk and no more power.

I can only guess to make it very reliable, it would seem it would be very easy to make much more power. Also maybe the turbo/super combo was done to keep the torque down. Just speculation on my part.

Typically these turbo diesels make nearly double the torque of the HP number.

Banks is real big on the "no smoke" campaign. The supercharger and twins isn't setup to increase power. They use it for throttle response and to clean up the fuel.

A 700 hp diesel is going to use less fuel than a gas counterpart. More btu's available in diesel fuel, and they can be run at near peak power for hours on end. They are way over built to handle monster torque.

Torque output is probably tamed down so some kind of drive could live behind it. If you increase the rpm at which the engine makes peak power it decreases the amount of torque. All about moving the powerband to where it works for the intended application.
1500 ft lbs. doesn't do much good if you need an 18x40 prop but can only turn the motor 3200 rpm. Just a matter of making it all work together.

Someone please explain to me how torque can be tamed, turned down etc? Because X Hp at X rpm = X torque, to my limited knowledge there is no way around that?

You can vary the power output at different rpm's to achieve a different curve but at the end of the curve it is till hp= T x RPM/5252.

The supercharger, you are correct it is for low end power to get on plane, Volvo did this a number of years ago. If you look at the turbos they appear to be old style non VGT's so with 2 there is absolutely no bottom end power they need the SC to make positive pressure to build some exh temp and then they can have some boost - this maybe very OLD SCHOOL but is practical and works great! The only disadvantage is you can see the SC does not have a clutch or whirlaway as to disengage it once the turbo boost overcomes the SC (that was done as far back as GM EMD diesel's for ships & locomotives).

The 700hp is 1.75hp per cui which is very high but liveable if in a typical pleasure application where WOT is not more than 10% of total hours. Probably 500 hr at most between OH. That gives you 50 hrs at WOT which no gas engine can come remotely close too at that HP/cui!!!

This is a good practical package still and it looks cool which is 85% of the game, Yanmars, Cummins, CATs just do not look sexy in a performance boat!

There is little difference in gas hp vs diesel hp at the prop - you all know the gas engine uses reduction gears so torque is multiplied. You all have read whether it's me, Weissman, Cookee, Hustler, OL (the 4 engine boat), RIK, etc, etc that the fast diesel boats use overdrive gears. Once the props speeds are equaled through gearing it's all the same.

I am sure Banks is testing that rail somewhere but it has not been to any diesel events in a couple years. To my knowledge the SC on diesel's is still a work in progress, i could be wrong...I just have not seen anyone make a big splash with a supercharger. Banks is still chasing the old tractor motor...

With tuning...

Habana,

I found some old threads with you discussing this. What would it take to do this in a performance application? I assume the engines, probably arnesons, and some type of 2/3 speed gearbox.

Would this type of setup perform the same/better/worse as a 700/nxt package? The reason I ask is because my truck only has 365 hp but with the torque it seems like it has a lot more.

with tuning? That's the smart azz answer and I can laugh at that :lolhit:

I read many diesel things on OSO in general and there seems to be, sometimes, an idea that you change the final torque numbers of an engine with same HP and rpm - that's what I would like to know "how that's done" because I can't figure it out?

The engine is the engine against the governor, only gearing can change the torque figure if measured at the output but it is still hp= T x RPM/5252?

Turbo sizing, camshaft profile, tuning via the ECM since this is a common rail engine. I was able to move my torque peak all over depending on my timing map. It's no real secret. If you want a stock rod duramax to live at 500-550 hp bring the timing in late and keep the torque peak over 2300 rpm and under 1100 ft lbs.

I was not being a smartass, it is really simple. Stop thinking so hard, you can detune the programming in a diesel with a flip of a switch, or by plugging in your software to adjust.

Think of the stg 2 kit from Whipple for lets say a Merc 600, the retune the ECM right...With EFI, or with other tuning software you can make these adjustments at any time.

My triple turbo truck made around 800 & 1600 when it was set on kill. 90% of the time i ran conservative tuning and it would run about 500 & 1100...This was with very simple tuning, EFI you can pull fuel out any where. Or timimg, or injector pulse etc...

I gotcha so even though the torque is higher the rpm is lower which makes the equation work the same as a gas engine.

The only difference would be longevity of a diesel and better fuel economy or would there be a performance advantage with diesel and a gearbox?

Can probably make it get out of the hole faster, until you break a drive lol

Which triple truck was yours? I had the Denali clone twin turbo truck.

The 06 dually with the 22.5 built by Wide Open Performance. The truck was sort of ugly....

I just found out DieselPower mag is doing a issue in in Feb or the next month on there 3 favorite issues / trucks...I guess they picked mine as one of them, i saw the cover this weekend and it is on there.

Post a pic of yours. This pic is before the triples so it smoked a little...
http://i190.photobucket.com/albums/z...p/EdgeDyno.jpg

Your first question is very simple, drives don't matter, transmissions don't matter, non of it is relevant for a basic understanding of what it takes to go fast in a diesel boat - this is all you need to know - in the same gas boat, how fast does that boat go with what Hp engines, what size props and how fast are the props turning.

That is your baseline, you need to be able to turn the same prop at the same speed to get similar performance - to better performance you need to spin either larger props same speed or same props at a faster speed - nothing here any different than you would do with a gas boat.

How you achieve what I'm saying is where gears, drives, etc, etc all come into play but you need the basics first.


Your truck uses gearing. Think about it this way, your diesel at WOT is a good 1,000 rpms under the diesel rpms. When you are running your diesel truck down the road you are much closer to your max HP rpm range the engine has potential to make full HP easier because of this. The Gas engine is much further away from peak HP you would have to accelerate the engine more to feel the power start to get stronger.

The torque on the diesel is greater at lower rpms remember what I said above, the peak Hp is at a lower rpm so as the engine accelerates you have to cross peak torque at a lower rpm as well - all your peaks are achieved at lower rpm's so the engine will always "feel" peppier? make sense?

Will those engines perform like 700's/NXT's - NO

They weight more, they have bigger trannies, will need OD gearing to run on an NXT, will sit further up in the boat - add all that together for the same Hp and it can't run as fast top-end.

BUT, you can run those engines at 85% for hours where if you run the 700's at 600hp for hour after hour you'll be calling SeaTow!

You miss the point and you know I like talking with you on here and respect you.

The point was much simplier than you are making it - people make statements how someone lowers the torque not moves it around. If you lower torque you have to change one of two parameters as well and those are either HP or rpm but the engine has to change you can not keep those 2 constant and have lower torque.

If you disagree please post dyno reports showing that and I'll eat my words.

Not any more...that relationship folded.

Thats something I plan on doing in the future, who did your build? I hope to have my full billet/suncoast allison soon

Yes in most cases HP will drop also. You can build a diesel to produce less torque, but that is a specific type of build.

here's the big equalizer and I'll give you Buzzi's rational, because after all he is a sly old fox!

The diesel will run at a higher % of full load longer (not total hours but hours at WOT) and harder than a gas engine can. back when offshore racing was "ocean" racing and Open/Class 1races were 150-185 miles long. The gas boats would run easy when the race started, they were heavy with fuel and knew that 50%+ would break and not finish, it was a game of endurance. As the boats burned fuel they could run faster and harder (more % of throttle)

Then here come Buzzi (who was not the first diesel guy by any means but read the rules a little better), his plan was when the flag drops push the throttles all the way forward and get out front. The gas boats are faster but they will not run so fast as to break early on. Make the gas boats chase me so they stay within striking range to pass us. They will have to run faster & harder than planned and will most likely break before catching us. If they are burning too much fuel they will slow down and at the end be too far back to catch up anyway.

Watch the old races, you'll see I'm right!

Ok we'll have a draw

ps I love your truck but in a manly way :lolhit:

My truck / turbo's were built for max torque. I am not a big fan of the high hp low torque build, i think high timing, high rpm, hopefully balanced...

Thanks i actually traded it in 3 years ago, after i parted it out.

Check this out...The setup is really bad for the track but still cool.
http://www.youtube.com/watch?v=dYAWC...cmMM5wDZlOZ2Ww

Fleece...Cummins with EFI
http://www.youtube.com/watch?v=bv8AxOU7IRg

I did it all. Motor, trans, turbo plumbing etc. only thing not done by me was the paint on the truck
Email me if you have questions about building one.
[email protected]

PPE did a couple boats with the duramax and Imco, but it was not that big of a hit, really hard to get on plane at a low RPM with out running a trany, and that take to much room. http://www.youtube.com/watch?v=dR3laaqKAjQ http://www.youtube.com/watch?v=Y4ugzTL2y1U

Looks like the Tommy Bahama boat did not work out it is at pier 57 without power. That pretty much answers my questions. Someone has to know the story would be interesting.