I think the boat will do what you want do. I'd probably crank them to 500hp just because I want to be faster than the next guy but you don't have to be.

There is a Super Hero 40 on here with 300 Cummins B's in her. I think they said she ran about 50-53 mph???

The 40 SH boats with a full 380 hp B in them and full of ballast (total weight 14,000lbs +or-) ran at 60 -62 mph with a slight reduction gear just above 1:1 don't recall but are in my notes some where.

That's why I say 70's is reality for 500 hp and 440hp is probably.

I think you won't the Hp to swing the 19's, there a BIG blade hard to get on plane with a big wheel but you have 1.30 gears so maybe??? Hey, worse case you take a little dia off them and go from there.

Joe Gere

JCPerf,

I know your an engine builder so what point are you trying to make with "People look for the HP#s to go fast.Torque is very important to turning a big pitch prop"?

That torque allows for a good cruise speed but Hp gets you there first?

Joe Gere

Torque lets you turn a big pitch wheel to get"over the hump" so to speak.It definately gives you a great cruise.If you have 500HP with 500 FT. LBS of torque and you have a boat with 500HP and 1000 FT. LBS or torque the one with the more torque will turn a prop with probably 4 inches of pitch more.Thats where your cruise and gas mileage will really shine

The 19 inchers are really big ,I have to grind some fiberglass away from the pulsdrive unit to have some clearence .

There is some suction built into the pulsedrive unit ,there is a hole that is been drilled in the shaft support (can this called a strut ? )a couple of inches above the shaft bearings in the fiberglass structure with a hose that runs through the inside of the box to the top with a thru hull ,plus the pulsedrive unit is trimmable

The exhaust gas from both engines can go out throught the pulsdrive unit ,and exits to the bottem of the box through +- 15 two inch holes.

I will first try and see how the engines will do when in stock form




Can,t wait to try the boat out.

If I'm not mistaken, all the old UIM Class1 turbodiesel raceboats ran 3 4 and maybe even 5 speed transmissions. Weismann transmissions were very popular. That would be one speed avenue to explore.

JCPerf,

How does anyone make an engine have 500hp with 500'lbs or 500hp with 1000'lbs.

If the Hp of both engines are equal the only way to have difference amonts of torque is to have them develope the Hp at different rpm's.

I know you gave an exaggerated example but what you describe is the basic difference bewteen gas and diesel engines.

My Round Britain 2008 raceboats performance figures:
36 ft Ocke Mannerfelt-hull
2xVolvoPenta D6-435(3700rpm) and DPR-drives
GR-9 propellers modified w 31" pitch
12000 lbs dry
75 mph with 1100 liters of fuel at 3700 rpm-could use larger propellers
On the 210 nm stage from Inverness to Edinburgh I backed
of once from WOT.
We drove the boat from Sweden to Portsmouth and Round Britain. 2500 nm together.
No problems whatsoever. The engines used 2 liters of oil during the 2500nm.

www.teamvilda.se

WOW...:cool:

I have a 43 Black Thunder with @ 650hp, 650tq. It's a little heavier than a 40 Baja but it's an efficient hull. With Bravo 1 26 pitch props at almost the same prop speed that you are projecting, I go 78 mph gps. It seems to me that your props are too big. The diameter is odd. Most sportboats with Arnesons are using something in the area of 17 dia. If the boat hooks up well, 26 pitch will be too much. You'll need more like 600 hp to turn them. I'd try something more like 17 dia. x 22 pitch to start. Maybe 17.5 dia. if you are more concerned with cruise efficiency.

It's easy to see what Habana Joe is saying about hp vs. torque. A HP500 running through a 1.5 Bravo 1 puts out 500 hp but torque is multiplied by the gearatio. So it becomes 500hp and about 800 lbs. torque at the propshaft. Now it seems more like a diesel.

You guys push me to look up to much old stuff!!!

ParriYacht is dead on the the SH's had 17" & 16.5" dia props with the Arenson's.

I can't find a pitch number but with that 1.30 reduction you have lots of torque to start spinning a prop with. After you shift into direct?????

I talked with Rik from Arneson(I found this guy amazing ,I have another brand surface drive ,and he took the time for me like I bought one of his) a while ago about propellors for my set up,his advice was to find a prop with a diameter as big as possible something like 18 inch or 18 1/2 and as many blades as possible ...I guess I have to try what happens ,like you mentioned ,I could let a prop shop cut them down to 18inch or so if getting on plane is difficult,or I need a little more rpm,s .

I like to know what sort propellorslip numbers I can expect with a surfacedrive like I,m using ?
suppose I turn 3400 rpm at 1:1 with the 26 pitch props ,and having 10% slip ,I would go around 75 mph ...

max horsepower is at 3300,so with 10% slip would be 73,5 mph, I have no idea how much slip I,m going to see ,I mean it could be like 6-8 % ,then yes the pitch is likely to big.

These Rolla props are harder to find ,and expensive too,this set was not that bad priced ,and I thought I could always let them modified by a prop shop.

The Baja 40 has a straith hull ,no rocker /hook ,I,m going to mount the weigh as far aft as I can ,such as the fuel tank can be built smaller ,like 200 gallons instead of 300 ,and mount the tanks as far aft ,just next to the first bulkhead that separates the engine compartment ,battaries close to the transom,etc etc Rik also mentiod these type drives always tend to push up the stern ,lucky the inner strakes stop at +- 10 -12 ft from the transom,and the hull itself is not really heavy .

A.J

Rik - is a wealth of information. He has seen so many applications with surface drives it's scary!!!

As far as slip goes, you got to be under 10% with big wheels like RIK suggested turning them that slow?

The bigger diameter the prop the slower it can turn to be efficient, small props need to turn faster to keep up.

As far as weight goes, the old Buzzi boats we ran plus the SH's with the diesels where naturally stern heavy because of the weight of the engines /drives. Our fuel tanks were in front of the engines and the longer range tanks were in front of the cockpit. With the diesels side by side there was no room in the engine bay for fuel tanks.

My guess is with the added weight you need the tank in the front of the engine room like we had ours.

RIK is right they lift the stern pretty good. We ran the SH's with straight bottoms no different than your Baja and they were fine - again your building a pleasure boat, it will run good for what it is I have no doubt.

Joe Gere

props
 

Joe ,I want to show you the props I have bought ,because I could not find any info ,and have not seen this type before .
Unfortunatly I can,t post here ,and can,t post them to you direct ,could you send me your email ?
Maybe you can post the pics ,so others can tell /help identify .

A.J

nice pics, the water looks coooooooolllllllddddd!

[email protected]

or

[email protected]

I'll crop and post for you, no problem!

Loud pipes save lives!!
 

My last Pete had a 600 Cat with 6" straights. Would come home on the weekends to twin 600's with dry pipes in my KV.

scarab kv - that's funny!:ernaehrung004:

Here are sterling's props

Bronze props will be easier to work than stainless for sure. With the size of those blades, your slip numbers should be wery low and getting on plane shouldn't be a problem either. Looks like a well thought out project. Good luck. Bam has a couple of formulas for hp to speed and prop slip you might want to look at. http://www.go-fast.com/bam_marine_knowledge_base.htm

We keep trashing the same stuff over & over. The Cummins 5.9L is a great engine. But we keep overlooking it's one obvious shortfall... "5.9L"! We compare it to gasoline engines with 1-1/2 times the displacement. It's the old rule displacement = more horsepower & torque. Dang ya'all are using over 8L displacement gasoline engines why not get into the over 8L diesels. A Cummins 8.3L will give ya 600 hp without exceeding the warranty. Ya'all scream about the weight but if you were to change some of the hull parameters to work with the extra pounds you can make it work. Also when you start down that path why half step? Try jumping up the 11L to 14L class engines. There are a bunch of good engines in that range. CAT C-15 ACERT, Komatsu 6M140A5 and a bunch of euro engines. I've seen a lot of patrol boats in the 40 ft class that cruise all day long at 50 to 60 knots and when you throw the sticks to the wall will squeeze out a tad over 70 knots. They are all running close to 14L displacement. It all boils down to engines and tatas bigger is better!:drink:

The huge torque the engines you mentioned produce would be ideal for boats with surface drives to go fast ,but I think a few things that come with these engines will not always work ,(atleast thats my opinion)

I think like you already mentioned the added extra weight of these engines compare to a QSB
And the gearbox that must be chosen must be some heavy duty unit to handle that torque ,is very heavy ,and can the gearbox manufacturer (s) offer gear ratio,s that can be used for these applications ?
I mean can the propshaft turn fast enough ?
Are all these engines you mentioned 6 inlines ?
And how wide are they ?
Can these type engines mount close enough together to keep the props in a resonable close distance from eachother ?

I don,t know if a Baja 40 ( for example ) can handle the weight from two turbodiesel cat engines and gearboxes ?

A.J

The engines are heavy a pair of CAT C-15 ACERTs bobtail weigh about 3 metric tons. http://marine.cat.com/cda/layout?f=200497&m=214842&x=7
But that didn't keep Buzzi from building a 42 foot sport boat that can go 70 knots with CAT C-15 ACCERTs. http://fbdesign.it/a42rib.php
:drink:
As for that Baha 40 a pair of Cummins QSC 8.3L 600 hp with ZF two speed gears and Arneson could be probably sorted out for a good running boat.:drink:

Two cat c15 ,s with ZF 550 two speed trans is dry weight 8832 lbs ,thats without drive system,cooling water ,I guess it could weight roughly 10000 lbs including the drivesystem and steeringparts etc.

I don,t think my Baja 40 is strong enough to handle that kind of weight on its stringers,I think most of these type boats are built to light for that weight.

Buzzi ,s boats are probably built strong/thick enough to handle that kind of weight, and held the engines/transmissions on its place and preventing the whole engine package goes thru the bottem when reentering


I went to Buzzi in Italy about 6 weeks ago to buy two ZF 110 TS two speed transmissions ,amazing company ,very clean ,they have a 5 axis milling machine in a 90 ft long booth where they do the plug milling .

I saw these Isotta,s 2050 hp engines ,these are amazing ,I almost could stick both hands inside the inducer from a turbo,the guy that gave us a walk thru the place said they have them up to 2500 hp ..

They also had Buzzi,s 4 engine boat overthere ,the engines were Iveco FPT , just a Cummins 5,9 common rail , on four trimax drives .

Hey ,good to have a diesel thread back here on OSO,I was getting bored about all that gas talk only

Stirling, who told you how much to turn up the Yanmar 440s to reach the 500 hp mark? I will tell you that a couple of years ago, I was apart of a team running a pair of yanmar 440s in a 42 fountain with asd 8s. The boat ran 87 mph and yes we had the motors turned up, but not just the fuel screw. be carefull with how far you go with the fuel screw.

Just curious, but why did you go with the Pulse Drives?

What year is your hull, and how did you come about with your weight calculations. Only reason I ask is that I think you will be heavier than your expecting, unless you have removed alot of weight from the boat.

What area are you located in?

I did a search hee on OSO on Yanmar 440 ,and read all post about it ,Supertermoli (OSO member)mentioned just turn up the fuel in one of his post ,he had a boat with four Yanmar 440,s.
I did go with the pulsedrive because it was a good price for the unit ,and I liked the platform above the propellors /shafts .

If I had not bought the Pulsedrive unit ,I would probably had used a set Arnesons .

The year of the hull is 2000,it is a lightweigh poker run edition and is all empty in front ,however I am busy with adding a small head/ and galley in front with a fridge .

The weight I expect is just a rough guess,I bought this hull with no engine /drives ,completely stripped from a theft recovery,it was a triple engine boat ,and I reconfigurate is to a twin engine stringer boat ,during the whole process of fiberglassing I found the stringers are made from balsapanels 2 x 3/4 inch thick glued together with epoxy and fiberglassed into the hull,the engine room has stringers from plywood 1 1/2 inch thick glassed in .
All the floors ,bulkheads ,reinforcements throughout the whole boat is made from balsapanels glassed in with bi/tri axial glass.
I could imazine this boat could not weigh that heavy ,by looking at the thickness of the fiberglass that is been used on the outerskin ,and innerskin on top of the balsa .
A rough guess would be 4500 lbs for the bare hull only .
The whole hull and deck is sandwich balsa tri /bi ax fiberglass
I found a few poker run editions on the internet ,some said they would weigh 9500 lbs with twin 500 hp big blocks with bravo 1 ,s .
The Yanmars are 1200 lbs each ,and the zf 2 speed 150 lbs a piece ,so roughly 3000 lbs for engine/trans the pulsedrive was 500 lbs complete if I remember .

So with fuel/batteries /all the other parts thats needed I came to +- 10500 lbs weight ,but I could be completely wrong ....

I,m located in Europe /Netherlands

Just curious what will happen if I turn the fuel up ? will the EGT,s be too high ? My idea was to run both engines with pyro,s permanently to keep an eye on things (even when stock output)

thanks for input

A.J

With the price of diesel fuel and the pollution laws that went into effect in 2007, it seems like light diesel development has stalled. My 2007 GMC Sierra Classic Duramax is the nicest truck I've ever owned. Looks like I might have to keep it for a while. I know that the auto makers were working on even higher displacement and hp light truck diesels. Does anyone know what's happening with those right now?

I read somewhere that Ford is going to make a diesel engine in a F 150 pick up,the F 150 was not available with a diesel before ,Dodge is having the 6,7 L six inline (cummins)for like 2 years now in the trucks .
GM, I don,t know if they were going to a bigger displacement /horsepower

Started the rigging this past week... :cool: The Cummins really fill up the engine bay...:eek:

Coupla pix....DTS controls...

Hey ,good to have a diesel thread back here on OSO,I was getting bored about all that gas talk only[/QUOTE]

hey A.j.

youre right we have to start a diesel section here on OSO !

shueman,

great engines saw them in person when I bought a pair of qsd 4.2 for my 32 hustler but they are very big ,will they fit in the standard engine room?

thx bor

Cost versus Benefit?
 

Shueman:

Hats off to Eliminator and your deep pocket customer who's bankrolling this project. It will be interesting to see if the trannies and NXT drives can take the torque and survive.
The real problem in performance boats with high performance diesel power will be costs versus benefit.
Would you give us thread readers a rough ball park of what this boat is going to cost the owner when finished, it will probably make most performance boaters reading these threads fall out of their chair!
If and when the truck and automotive industry come up with lighter more cost effective diesels there will may be a place in the industry for performance diesel boats. In the mean time its just a very select few who will want to step up for the huge dollars it takes to make these boats a production reality. Glad someone is going deep into their wallet here, it becomes a wealth of information for the rest of the industry on how it may become a production reality!

Keep the info info coming as well as some facts like the weight of the engines and such, and of course the approximate price realm of this beauty!

Best Regards,
Ray @ Raylar

you don't want to leave the temp probes in permantly, they will most likely eventually burn up and send pieces of metal through your turbos. Once you get them set pull the temp senders out. I can say that we turned the engines up a bit with the fuel screw, but you can also turn up the no load rpm which is supposed to help with mid range acceleration, as well as give you more rpm to play with. What temp were you told was ok to run the engines at?

Where do I lay down my bet?
 

Lets see...... Cummins QSB 5.9 480hp has 940 ftlbs of torque output and the NXT input torque is rated to 800 ftlbs. Ray you holding the pool on how fast it breaks? I would've gone with 6s they can handle more input torque than the QSB has.

Keep the dirty side down:drink:
Ed

Dude,
It's looking great! But I think it would've looked even better if you had the heat exchangers chromed ;)

Whoa!!!
 

First! the normal position of a pyrometer is on the outlet side of the turbo in the event of a failure nothing goes through the turbo.
Second! pyrometer probes can handle temperatures of over 1500F. If it ever got hot enough to destroy the probe the engine would've had a meltdown first.
Third! diesel engines are real easy to destroy by over boosting or over loading. That is why a pyrometer is just about always installed. The pyrometer will give you a heads up before anything else that your heading for something bad.:eek:

O Brien

I havent found much info about the max temp range for the 440,s , What temp did you have on the 440,s ?

Were the 440,s you used then ,relaiable ?
Did you broke stuff ?

What rpm did you run for long periods ?

thx A.J

You beat me to this, couldn't say it better myself - good catch as always!

On my old Ford F 250 ,I repaced the probe from after the turbo to pre turbo ,and saw a 250 degrees difference in temp
Before the turbo its a little hotter,its not something to overlook when on the edge.
The bolt that can be removed to install the pyro on my Yanmars are pre turbo as well.

I run the probes in my outboards powered catamaran also all the time ,and I have never lost a piece probe .
Even when I had a #5 cilinder meltdown and the piston came out the exhaust port in liquid form the molten ali sat into the exhaust port right on top of the probe .

how about a pre and a post turbo gauge?