leviathan

You can get a 410hp supercharged version of the GM 6.5 (hummer motor) from sweden, which would probably be OK on a modified bravo.
I have a pair of turbo/intercooled 6.5's making 325hp a piece on bravo's, the boat runs 71mph.

STV_Keith

Groove, depends on what kind of power he decides to put in that thing. The 5.9l Cummins has TONS of potential. I work for a high-performance diesel outfit called Diesel Dynamics and we have pickups with the 12v Cummins making 800rwhp on a dyno on just #2 diesel. That's about 1600ft-lbs and is daily driveable (except for tire wear )

When LT gets it together, I'm sure we'll be helping him put the power in. Hell, that rig had twin turbines in it at one point...he's not one to go slow.

groove

I totally agree with the potential. I think the difference is a boat is a little more like a truck driving around with the brakes on all the time (and going up hill ) The trucks on TDR are great and I've been a member over three years there.

Lets face it, a 1 ton truck pulling a 20,000 # trailer is nothing like a boat running near top speed. You need a good amount of power to get going and then a small fraction to keep it going.

The trick is to build a boat with a diesel that can sustain high boost over a long period of time.

Not sure where that point is with the Cummins. If I remember correct Cummins sells a 370 hp marine B motor. I was guessing you could bump that up to 450 hp safely, getting years of hard use.

STV_Keith

I don't feel that sustaining high boost for a long period of time would be a problem, especially with the size of intercoolers available to the boat (the water it rides in). You could even go as far as going to water cooled turbo's to increase longevity.

Load is exactly what the diesel needs to keep the boost up, where it is efficient. It think it is very suited to this type of application. I think 750fwhp would be no problem.

shifter

cobra860,
What rotation are you running?
There is a company in Oslo called Craft Marine. Jann has a lot of diesel propellers Trimax drive parts and Seatek parts. 47-911-85000 is his number.
He might have someother props you can try as well as tweaking the engines for more speed.
pat W

velocity260

Cummins diamond series have 420hp, big motor though thats what my dads 50'carver has in it.

cobra860

Thank you shifter, I will pass on to my friend the info, so he can deside what to do.

I have my self a 6,5 "hummer motor" from sweden.

The name is marine diesel and the engine I have is a hammerhead with compressor on top.
Run it on a bravo1 with 1,36 gearing and are at the moment testing out propellers on it.

here is some pic of my boat.

cobra860

pic of the hammerhead diesel engine.

leviathan

Hey, cobra860, that's a 300 isn't it? I've got the 410 (the first one infact) which has the bigger blower on it, am currently fitting it in a B28 batboat for a customer, it's going on a bravo one with a few imco bits, torque is gonna be pretty high, so time will tell if the B1 is up to it.

How quick does your boat go with the 300? and have you had any trouble with it? and, what is your drive height?

Take a look at www.boatmad.com a UK/Europe site for performance boaters, it also has a forum.

groove

And I didn't think anyone was into diesels. You guys are a step ahead of me. Your boat looks great.