Getting a duramax to last at 1000RWHP

x MadMAX DIESEL

<<<< No Horsepower
Dec 30, 2008
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if need be id go with stroked verus bored out if you only do one. like you said a prop is harder to turn than a wheel, and long stroke engines have it in their blood to make torque.

jw would you have the exhaust exiting in the water? that'd be some skanky lookin water afterwards lol
 

whitetrash21

put on da damn helmet day
Apr 29, 2008
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When we run just over 1000hp, to the tires, our egt's run right about 1500*. With a water to air IC and cold water I bet it would be down around 12-1300* if not a touch lower. I know with different turbo's you could get it even lower but the lag would be worse. For something like this you'd probably need to build a bunch of parts to make things as efficient as possible for the lowest egt's. For sustained use the coolant temps would be a big concern.

One thing people probably aren't taking into account is that the ratings on the other motors are at the crank. So that would be about 800hp to the ground in a truck. At that hp level I'm sure we could keep the egt's in check and long as you could keep the charge temps cold.

Running a bigger turbo will equal lag, but on a boat, where its gonna be running 80% or more throttle a big majority of the time, I dont think it'd be as big an issue as in a truck. We talk about lag because we have to get a 8000 lb truck moving 50-100 times a day, not so in a boat where, as Wolf said, it will be running flat out for hours on end.

JMO, but I think one could get away with a huge turbo boat with minimal affect. Even watching BB gasser boats accelerate, it takes a while to get up on plane, especially when it weigh 9000+ lbs. Not like a diesels acceleration would be any different with the correctly pitched/sized prop.
 
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WolfLMM

Making Chips
Nov 21, 2006
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Marine engines have a "Wet" exhaust, how does that work in turbo charged applications?
 

x MadMAX DIESEL

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Dec 30, 2008
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not sure, but i would have it leaving out of the water... a nice little 7 inch miter cut, cut thru the fiberglass coming right out the back lol taht would be saweet
 

turbo_bu

Member
Mar 27, 2007
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Marine engines have a "Wet" exhaust, how does that work in turbo charged applications?

Basically, it will just increase the back pressure .... not good for your turbo(s). I would do just like the jet boats, straight out the back :)

As for keeping the charge temps down, a water to air "appropriately sized" will do the job just fine. The key will be sizing to live at the delta temps. needed without creating too much a pressure drop across the core.

As was already mentioned, there are things you can do to get the boat going if the turbo(s) are so big that they will have a lot of lag. I've seen a european diesel open boat class that had to inject air under hull near the props so they could get spinning fast enough until the engines got spooled up. Otherwise ... it was going no where fast and leaving LOTS of black smoke.
 

x MadMAX DIESEL

<<<< No Horsepower
Dec 30, 2008
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Lexington, Ky
you could try to get some type of brake system somewhere on the driveline to create a way to build boost off the line.... but something would fail soon prolly, and would need to be serviced quite a few times.
 

Idaho CTD

Junkie
May 28, 2008
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Marine engines have a "Wet" exhaust, how does that work in turbo charged applications?

Usually on a turbocharged motor the exhaust housings, manifolds, and/or some of the plumbing is encased in water. The isn't any water directly in the exhaust. The down side is it can take out some of the heat that drives the turbo's which can create more lag.