New Cummins/Mercruiser Project
10-03-2008, 11:54 AM
#61
Registered
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!
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
10-03-2008, 02:49 PM
#62
Registered User
Join Date: Feb 2008
Location: West edge of the Pacific
Posts: 610
Likes: 0
Received 0 Likes
on
0 Posts
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
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
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
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.
10-03-2008, 04:09 PM
#63
Registered
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
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
10-04-2008, 12:16 AM
#64
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?
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?
10-04-2008, 03:47 AM
#65
Registered
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?
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 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
Last edited by stirling; 10-04-2008 at 03:50 AM.
10-04-2008, 07:47 AM
#66
Registered
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?
10-04-2008, 10:08 AM
#67
Registered
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
GM, I don,t know if they were going to a bigger displacement /horsepower
VIP Member
The Cummins really fill up the engine bay...
10-04-2008, 11:57 AM
#70
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
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
