Volvo Penta IPS

[TrendSetter]

Ok so who here has seen this thing first hand? I know they got the public veiwing of it in a few weeks, and it will be under a Four winns, a Cruisers, and a Tiara. seems to be very intersting set up they have there. still think prop manufacers are gonna be the big winners here annualy, then the guy who gets to replace the whole lower unit cause it is sacrafical. Just curious what everyones elses thoughts are. the perforamce looks awsome, handking should also be sweet. here is a link to the artical IPS (http://www.ybw.com/auto/newsdesk/20041101132742mbynews.html)

[gonzo]

If an imboard powered boat where to hit the ground as hard as those drives need to break off, the struts would probably get driven into the hull. Overall seems like a good design. If you want more protection the boat can have skegs, like some inboards do. However, it would loose the high performance edge.

[kapnD]

I like it! I have toyed with the idea of a reversed v-drive to put the propellor in clean water for maximum efficiency, but the angle was bad and the rudder impossible. The volvo unit is clean and compact, and duo-prop efficient too. I agree with Gonzo that the breakaway design could certainly minimize hull damage in grounding or collision. I also like the fact that almost any "outdrive" system integrates propulsion, cooling water, steering and exhaust systems in one installation, definately a cost savings over conventional inboard installation.

[tom kane]

Designs change but the principle remains the same.1950`s and there was a steerable model with no rudder.

[Dunkan]

I've seen it
I've driven it
I love it...........

[Capt JD]

Just delivered a cruisers 40W/IPS and it's unbelievable.
Its Grrreat

[Richard Petersen]

I hope they come with a sonar alert system, for the rock shoals we have in the Saint Lawrence River as it goes thru the " Thousand Islands ", all rocks. All mechanics may no longer go home on Friday nights. Tow Boat USA, liberty is cancelled. We HEAR KLUNKS day and night.

[Richard Petersen]

A big block Mercruiser stern drive unit is less than a propshaft and rudder? Where, Who? The fact that only dual drive and upscale boats get them should tell you SOMETHING about the prices. My medication is ruining my suspicious mind. UMM UMMM.------I need a BRONZE magnet for salvage work.

[ABoatGuy]

They are actually designed to break away without endangering the vessel. Hit the same rocks with conventional drive train gear and you also have a big expensive mess.

[gonzo]

Richard:
All it takes is a look at the charts, the shoals are marked in there. You seem very negative about new technology. What you like was new at some time too.

[Richard Petersen]

You are mostly right on that. I have a much deeper and proven distrust of product claims with age. Very difficult to scam a more experinced consumer. I should be very suspicious where my money goes for a claimed product. Rich

[Richard Petersen]

I am having a devil of a time finding enough reasons NOT to use a out of sight jet drive on the next boat. Different docking power levels of the engine is all I can come up with. Rich

[Chuck Bates]

Here's another link to view this drive:

http://ips.volvo.com/volvopentaips/

[TrendSetter]

the new drive system sounds intersting, and i think when they rip off the bottom like they are designed to.. volvo is banking on this so they can upsell a new unit... Now i am just waiting to find out more about this and get cert. in doing these so i can start bank rolling in this. however its nto all big money boats putting this in, Cruisers and Four winns are far from big money boats and they are both getting said drives... now if only my Tiara sources would fill me in on this system some more

[woodboat]

They're not demoing these in boats that would be in the flats fishing!!!!!! What makes everyone think they are going to be ripping these things off left and right??? They are designed to replace inboards in boats 40+ feet. I have never even damaged a prop on my inboards because I never beach it, that's what the dinghy is for. If someone goes running these things aground they have more money than brains anyway.

[tom kane]

Waiting for some one else to build the drive that suits your pocket and your needs most,and you probably will wait for ever.The only way you can get what you need is to design and build to your own specifications.This is not impossible and the costs of one off building need not be high.Look at the auto trade and see how many vehicles are the same design,and the designs change almost over night.Perhaps boat building should learn from the auto trade.There is much more variety now than a few years ago and boat designers are starting to be inovative,but there is plenty more scope available.Modern autos have many more components than older ones and still achieve good economy and the extra bits and pieces do not slow them down.There is a lot of room for improvement in modern inboard/outboard drives and their motors.

[TrendSetter]

woodboat, come on your on the chesapeake you should know better then most, I work down in annapolis way, and i woudl say average about 2-3 boats a month will get hauled at our marina alone from people hittinng bottom, dead heads, or whatever else is out there...its just facts of like... i can recall this summer alone 5 different boats who hit so hard not only was there prop damage, there was severe rudder damage, as well as structrual from the upward impact.. this is what leads me to believe I am gonna be makin some money slapping these things on... I just wanna know how much these things are gonna way, cause Bravo III are to damn heavy bringin one of these up from the bottom could be a real bear. however having said all that, i dig the idea, i like the results they are showing and in time this might be the next "big thing" but if it is time will tell, and a sure fire way to know if this is gonna be it or not is watch what merc does if they follow, they will likely make it simpler... and maybe even better just look at I/O's from 25 years ago for your answers i guess

[Willallison]

As Gonzo suggests, we are all predisposed to a little (healthy or otherwise) scepticism, and given that Volvo aren't exactly a back-yard operation, I'm sure they've done their homework and the IPS will be at least somewhat successful. Then again, one would proabaly have said the same for OMC and FICHT.... :eek:
Personally, I think the system is fundamentally flawed. Any new drive unit that has two very expensive props as its 1st line of defence is a bit suss. But when it's secondary defence is to send the entire drive unit to the bottom, I'll keep shopping elsewhere.
All the performance figures that I've seen compare the IPS to conventional shaft drives. How do they compare to larger sterndrives? Konrad make drives for larger engines ( http://www.konradmarine.com/products.html ) My guess is that there's not much in it and I'm sure that if Volvo had put the same level of resources into developing a larger duo-prop unit, the difference would be even smaller. And whilst sterndrives are still somewhat vulnerable, at least they don't fall off the first time you run over a submerged log! :eek:
The reality is simple - IPS is a marketing gimmick - a very efficient one perhaps, but no more... :eek:

[woodboat]

I stand by my words about ripping one off and having more money than brains :) I grew up on the water. It doesn't take long to figure out that where the river takes a turn it is shallow on the inside edge :) The crabber two doors over goes out everyday, he never runs aground. It is gonna be the weekend boater, driving a porche, with the brand new Cruiser Yachts that hits bottom and rips one off, not me. I didn't say they wouldn't be getting ripped off, just stating who it is that will be doing it :)
Maybe I should get into the marina business, looks like business will be picking up.

[TrendSetter]

you wanna make money in the marine industry start off with 2 million and get out quick if your lucky you got 1 million left.... Sea tow dosnt have a ton of boats running all around the bay cause business is slow. 90% of boaters out there are the weekend warriors ergo these guys will be bringign in tons of business i guess

[woodboat]

Do you work in a marina in Annapolis? Do you own one maybe?
Rob

Oh, my favorite thing is to take the boat to a nice restaurant on a weeknight. Weekends I rarely travel far.

[TrendSetter]

not in Annapolis, I cant stand the Ego's there. a little further south of there is where my shop resides. I am not an owner just a mid level personel

[woodboat]

Always interesting when on the vast web you find someone nearly down the street.

[TrendSetter]

yea this is twice this week for me scarey, some times.

[Richard Petersen]

Will the props that fall off, fit on the shafts of the ones that do not? IPS look SOOO nice and shiney.

[Willallison]

I stand by my words about ripping one off and having more money than brains :) I grew up on the water. It doesn't take long to figure out that where the river takes a turn it is shallow on the inside edge :) The crabber two doors over goes out everyday, he never runs aground. It is gonna be the weekend boater, driving a porche, with the brand new Cruiser Yachts that hits bottom and rips one off, not me. I didn't say they wouldn't be getting ripped off, just stating who it is that will be doing it :)
Maybe I should get into the marina business, looks like business will be picking up.

I beg to differ - somewhat at least - I've done plenty of work surveying commercial boats that have run aground. Sure, if all you ever do is jump on your boat (commercial or pleasure) turn the key and head out the same old inlet into deep water and go fishing, or potter from the marina where you keep your boat to another where you eat lunch, then chances are you wont bump the bottom. But do any real cruising and chances are that you will eventually hit something - whether itis an uncharted rock or a submerged log.
Hopefully, if you're running sterndrives they'll kick up on impact and you might have to change over to the spare prop (you do carry one I hope... ;) ). With conventional shafts you at least have the option of the protection offered by a keel (or two)

[woodboat]

First off there is some smileys and a bit of tongue in cheek.
Have you seen damage often that would be hard enough to rip off one of these units?
My current boat has inboards but a single center keel offering little protection to the shafts and props from say a log. Surely prop damage has got to go up. I question if the common damage will be catostrophic.

[gonzo]

There seem to be many negative but unqualified coments. This unit is for high performance use. If your budget doesn't allow you to own one, it shouldn't drive to sneer at those who can. Manufacturers sell what the market wants or needs.

[Richard Petersen]

Right Gonzo. I think the Merc duo prop is still a option on most boats.

[gonzo]

Yes, they do. In the subject of spare props, Volvo among others offers an emergency plastic spare. A duoprop set is about U$100.00. It is good up to 25 mph. Finally the marine answer to the donut spare :rolleyes:

[TrendSetter]

I would not say this is a HIGH PERFORMANCE option.. as much as i would say an performance enhancing option. i like th idea and in time i hope it works other wise much like some of there old junk i am stuck working on I am gonna point laugh, then cause and say the sweds should stick to things they now like porn. My hope is A] they make a full composite version of this and B] merc follows step and this way we both win cause there is compation.. just look how long Duo-prop was around before merc jumped on it and improved it

[Willallison]

Woodboat - I have certainly seen damage that would have ripped an IPS off. I'm not suggesting that the IPS is any more or less vulnerable than conventional shafts. My criticism of the unit stems from the fact that Volvo started with a blank sheet of paper and have failed - in fact virtually ignored - the fundamental weakness of all drive systems bar jets...their vulnerability to damage from impact.

Gonzo - it really depends on your definition of high performance - if a 25-30 knot cruiser is a high performance boat, then I accept your point....though personally if I could afford a Ferrari I wouldn't drive around with the doors open simply 'cause I could afford to have them ripped off! :D

[Richard Petersen]

We will never know if it is " better", as none of us will ever get to test 2 boats rigged side by side. No one is THAT impartial.

[Richard Petersen]

Foward facing props??? I just woke up from a long sleep during the end of WW II. Everything that flew then was being made into a counter rotating prop job with up to 5 blades per prop. Why?? Because you are overpowering the machine so much, that torque is taking control, of the direction of travel. Dumb dumber and stupid. What is the next improvement? 4 counter rotating props? LUV IT LUV IT LUV IT.

[TrendSetter]

I dont knwo about never, go run down to your local Tiara, Cruisers, or Four skinns dealer and take them for a spin, I am guessing some of your more big time players in this market will pony up for side buy side comperisions

[Chuck Bates]

According to Volvo some of the highlights of this new propulsion system include:

- Twin engine installation only
- suited for 37 to 50' boats
- nibral (nickel/bronze/aluminum) alloy drive and props to limit corrosion
- EPA 2006/07 approved
- One supplier for complete package
- No shaft alignment needed
- Faster to install
- Reduced installation time, one person required
- 12 & 24 volt systems available
- Integrated water pickup
- Integrated exhaust system
- Rudder indicator integrated in system
- Part of Auto pilot system integrated, interface from Volvo Penta fits Raytheon, Simrad, Autohelm
- EVC (Electronic Vessel Control) display standard at every helm station
- through drive exhaust which results in it being expelled in the wake far from the boat
- Increased accommodation area which may be enough to add another cabin or more to the existing interior layout
- Flexibility in interior design
- over 40 different patents pending

Steerable propulsion units enhance maneuverability:
Maneuvering a 40-foot boat in a congested harbor is not always easy. With a conventional straight shaft, steering capacity at low speeds is severely limited, since the rudder can only steer part of the propeller backwash – most of the thrust propels the boat straight ahead. Handling a boat of
this type is complicated and demands considerable experience. The 40-foot IPS powered boat feels like a 25-foot boat.

They tested the differences between a IPS-500 (370hp) twin-powered boat and a traditional TAMD63P (370hp) twin-powered prop shaft equipped 41' Cranchi and found:

IPS 500 - Top speed 37 knots
Traditional - Top speed 31 knots

Acceleration time to reach 25 knots
IPS - 13.3 seconds
Traditional- 15.3 seconds

Fuel consuption/range
IPS - 95 litres per hour
Traditional - 135 litres per hour

They compare the performance of a 370hp IPS unit to a 500hp traditional shaft drive.

More info at: www.volvopenta.com/ips/gb

[woodboat]

I don't know that low speed maneuverability is that much better. When docking I basically become a tank commander and can pivot my 50 footer on it's axis regardless of wind (well within reason) I agree it probably drives more like a car and if one were to try and dock with rudders only I could see a problem. My rudders are pretty useless when docking.

[Richard Petersen]

The PR people rig another test to make their product SO much better!!! WE are much better than a old fashioned angled down shaft and propeller drive setup! Are you 30% better than a Mercruiser I/O? 30 % better than a OB? 30 % than surface drives? 30 % better than a AIR BOAT? YOU are 90 % better than a pair of oars.They really think we are dog do do.

[TrendSetter]

Ok so i gt some funny news, This engine has to have a boat designed around it, hence the new Tiara Sovern going to be shown in FL here in a few weeks... guess they got some big time backing on this with some major companies willing to step up to the plate

[Richard Petersen]

TrendSetter, I traced the paper trail back.It seems that the engines are the same family,TAMD63P. Shaft drive is rated as a rating 4--370 hp @ 2800 rpm. BUT--IPS is rated 370 hp @ 3500rpm. Why the difference. No TAM has a speed rating of 3500. Special Catagory of a rating 4 engine. I have to stop sleeping next to dog litter boxes.

[Richard Petersen]

I really believe the IPS is a more eff. system than a shaft that can not be trimmed up. :) Ican e mail the pages to anyone. Rich

[TrendSetter]

is that dog litter your sleeping next to r is it just the sweet smell of the garden state..lol... Yea i was noticing the same thing a higher reving engine maybe cause it is a rec. engine?

[Richard Petersen]

I have to credit Volvo. The PR guys are honest. Just read all the print. When do they go up against I/O's? The IPS could still be 1 to 2 % faster. :eek:

[TrendSetter]

but honestly why the hell would you want an I/O on big boat, even more so why would you want I/O's on something like a 40' Tiara thats gonna cost around $450k large min. guess its just me but I/O's are great for small boats, and great for me as a Marine Mechnic... but not for big boats.. again maybe its just me

[Willallison]

but honestly why the hell would you want an I/O on big boat, even more so why would you want I/O's on something like a 40' Tiara thats gonna cost around $450k large min. guess its just me but I/O's are great for small boats, and great for me as a Marine Mechnic... but not for big boats.. again maybe its just me

There are lots of reasons why people would want sterndrives - the ability to explore skinny waters, higher top end and cruise speeds &/or more economical in terms of fuel consumption, and most of all - increased amount of space that can be given over to accomodations. Granted, legs tend to be more expensive to maintain, but 1 or 2K per year for a leg service isn't likely to upset too many owners of 500K boats....

[Richard Petersen]

The best cabins in a big cruiser are always in the stern. I would never give that up to engines and drives. You brush the rocks in a cruiser.--- LIFE BOATS and ANCHORS AWAY.--- MAYDAY, MAYDAY, THIS IS NOT A TEST. Rich

[ABoatGuy]

Trendsetter,

In so much as the stringer arrangement and the ring where the pod is bolted do have to be designed for the IPS, you are correct, the boat has to be designed for the units, but any boat has to be designed for the propulsion system installation it is using. As long as the basic hull meets the Volvo criteria for deadrise etc. and the arrangement will work around the drives, they are adaptable to normal hulls. There is also a jack shaft arrangement available to put engine in a more "normal" location.

If you get a chance run a boat with one before you judge it. They are pretty amazing. Only time will tell if it all works over the long run. Inovative if nothing else.

[TrendSetter]

Ow trust me I am waiting for them to show up out here in the Chesapeake to see for myself. I totally dig the system, the theory of it is good as well, and I am always a sucker to try the new thing

[Greg Beers]

i see i'm a bit late to this dance, but does anyone have an idea of the cost of the ips? on top of the in line 6 i mean!

[PowerTech]

I herd the compleat drive system alone is 35,000.Thats with out the engine.

[Greg Beers]

thanks. that's about what i thought.

[PowerTech]

The drive is made to snap off on impact so not to sink the boat.I know that this thing is nuts but it is for the super rich.And the rich can't get enough crazy shiet

[Chuck Bates]

Carlwun,
Where are you getting your info?? A local dealer I trust priced it for me. It is $2000.00 more Canadian different for the sterndrive version of the same model engine. It is certainly not just for the 'super-rich' as you suggest. There are a limited boat builders now putting them in. Four Winns, Tiara, Cruisers, Carver, Cranchi are some. I can guarantee there will be many more. If anyone is interested in this product, ask your boat dealer what the difference they would charge between the traditional system and this state-of-the-art system.

Some advantages to keep in mind if it the IPS does cost more:

fuel economy - a 370 hp IPS performs like a 500hp traditional
cabin space - one more room can be added on a IPS powered boat
exhaust - thru-drive on the IPS. Thru-hull on the traditional
5-7 decibels quieter
superiour handling
etc. etc.

As you can see, I'm sold on this unit. If I was in the market for a 38-50' boat I would definitely look at this power. The dealer I talked to drove the 41' Cranchi that's in the ads Volvo uses. He told me it felt like a 24' runabout. He said it was fun to get behind the wheel of a 'sportboat' again.

[PowerTech]

I geus if it only cost 2 grand more it is because volvo is pushing the hell out of them to boat builders and just about giving them away.The price of the drive is 28,000$ exchange that is for the uper and lower sections and they are not availible seperate.I am sure the price is alot more if your old lower section is at the bottom of the sea and you cant retrive it for a core.The unit is not available by it's self new only as a package with motor.

[gonzo]

You are saying that the package is $28,000. That's not bad. As for VolvoPenta dumping engines, that borders on libel.

[PowerTech]

no the pakage is not 28'000$ the drive is that price as a replace ment for a broken one with a core thats what i meem by exchange.What i meen by giving them away is just that i am speculating that volvo is giving the manufacture a good deal to get the product sold.I would not call that dumping just smart buisness.I am only even speculating that because that dude chuck something from canada said he was told a boat with IPS cost only 2 grand more that a regular one.That could be B.S, for all i know.Or if that is true the boat buyer is geting a hell of a deal.And if that is ture someone is doing some discounting maby the boat builder is giving the boats away I dont know.All of that money will come back to some one first time the thing hits a rock.I have no knolige of any one dumping anything I am just talking motors here. the word liable makes me nervious.I am only speculating scenarios on what some dude herd in canada.no offince :)

[Chuck Bates]

Carlwun,
A couple of things bother me about your comments:

- Where are you getting the figure of $35,000 for just the drive? My local dealer here told me it would be $38,000 US total for the whole propulsion package. Engine, drive and instrumentation! Mind you, who cares how much the drive costs? The insurance company would take care of the replacement of the drive if it was sheared off anyway. If I was involved in a heavy impact with either powered vessel, I'd rather be on the boat with the sheared off IPS unit. At least it's still floating!

- As Gonzo suggests, dumping product is illegal. Since Mercury lost to Yamaha in their alleged dumping case, maybe they could go after Volvo as well.

This product is available in new boats only. Some of which I've listed above. As I suggested, if you are interested in this product, ask one of these boat dealers what the difference would be in price between the IPS and traditional shaft power. Keep in mind you will be getting extra square footage cabin space, and state-of-the-art power with the IPS unit. There will certainly be an upcharge for these benefits.

Instead of speculating, as you admit above, get your facts straight before you post them for the world to see.

[Willallison]

I think you guys are getting a little carried away here.....
Personally, I'd be surprised if Carlwun is far off the money with his comments: OK Gonzo, so you sell Volvo's stuff - it's only natural that you'd be keen to defend their product. But giving a product a price-point that is below what you'd ultimately like to sell it for isn't exactly dumping.
I'm on the record here for saying that I think IPS is little more than an extraordinary example of marketing-led engineering. I'm yet to see, hear, or read anything to convince me otherwise. Sure - it's more efficient than traditional shafts - but where are the figures to show that it is any more efficient than an outdrive? Why didn't Volvo spend the money on developing a bigger, more efficient leg, which doesn't fall off the minute you bump into a sand bar?
I may be way off - I have great respect for most of Volvo's stuff - hey even their cars are getting better! :D - and if I can be convinced otherwise, I'll happily eat my words....

[PowerTech]

I hate like hell that I may of siad any thing that may Imply dumping.I hardly even know what that means Exept for a distributer over stocking Tier 1 engines to sell cheaply to comerchial costomers that are not supose to get them anyway.I just know that a replacement IPS is 28'000 bucks with a core.I herd the unit is worth 35'000 but not avialible by its self. only avialible for a replacement or on the back of a new motor as a package.All that talk of mine about big buisness dealings and buying and selling is me just speculating for the sake of bull shiting.I qustion your price figures. My family buisness is a deisel sales and service center that is dealer for almost a dozen manufactuers including volvo penta diesel with rapid responce certification.2'000 bucks don't get you mutch around here but a oil change ,Impelors,some filters and a valve adjustment for 2 motors give or take Whatever other crap.I repete I know nothing about engine sales to boat builders or boat builders sales stratagies.And I dont know what a cup of coffie cost in Canada!I am not for or against IPS or anything else I could care less.I spend most of my days below sea level in a bilge I don't care what it is if I am looking at something it's because it is broken.The truth.Peace ;)And pleace don't bring up aligations of dumping or liabilities agian please I don't want my nut's in a vice.Thanks dudes lets talk motors.

[woodboat]

It is not unusual for repairs/replacement costs to far exceed original pricing for various reasons. As an example try building a car from the parts you buy to fix it. You will run out of money long before you build the car.
You have a new product. That means new tooling in the factory. So you get a few builders to commit to the product and set plant capacity to match. There is little left over for replacement drives. Certainly none availble as a retrofit. If it is a hit, production will ramp up, supply chains will fill and prices will effectively drop. I say effectively because they may simply hold fast while inflation goes up. Either way in a few short years they will either be gone or easily purchased by all. Simple supply and demand at work.

[jameshogan]

I read a write up a few weeks ago. A test.. two identical boats side by side. One with the new volvo and one with a traidtional rudder type engine setup. The author posted some figures and the IPS was actually worse or equal performance than traditional at lower speed and rpm (in refercne to fuel consumption and speed). Once you hit very high RPM, the IPS showed a small amount better. Fuel consumption was slightly less, speed was slightly higher. Ill try and find the article as I dont recall exact details. BUt bottom line when I read the figures is that volvo is doing a hell of a job on marketing and less of a job on actual merit. Any perofmrance gain would be achieved at RPMS seldom if ever ran by boaters.

Why are builders putting them in? Easy answer.. they are easier to install. One call and every possible piece a builder needs is sent. Why are companies accepting them though claims are exaggerated? Another easy answer. Foolish and uneducated consumers are always looking to buy snake oil.

I dont think these are necessarily bad engines. Just not what they are claimed to be. Are they any better performance? Maybe slightly in some situations. Are they any better for dealers/builders? yes as they appear to be much less $$. Are they better for consumers? Only if the savings is passed on which I frankly doubt.

My one big issue here is if I have a traditional inboard setup, I can repower with just about any engine. With the IPS who knows what will happen down the line...

[Chuck Bates]

James, is this the test with the Cruisers 400 Express you're speaking of:

http://powerandmotoryacht.com/engines/0205volvopentaIPS/

This test found:
- a 12% increase in speed compared to Volvo's claim of 20%
- a 16% gain in fuel savings compared to Volvo's claim of 30%
Handling/noise/vibration:
"Cornering at low and maneuvering speeds was even tighter. Vibration was virtually eliminated, thanks to the O-ring isolation of the IPS’s underwater units from the hull and the soft-mount installation of the engines this isolation facilitates. And sound levels were reduced, too, especially on the lower end of the rpm range."

In this application, Volvo's claims are exaggerated but still impressive. The test they did to come up with their figures was on a Cranchi 41. I'm sure the Tiara Sovran and the Four Winns 378 Vista have different test results again. The fuel savings alone stand out. Hypothetically, say these units get 10 gals per hour x 2, the IPS powered boat would save hundreds of dollars over a boating weekend. Over the whole year the savings would be phenomenal.

Add the increased salon room, virtually no smoke, and responsive steering, it seems like a winner to me. It's not for everyone. Personally, I welcome new technology. Others like to work on their 1972 Firebird with the carbed 350. To each his own.

[FAST FRED]

"It's not for everyone. Personally, I welcome new technology."

You may be less cheerfull after the first grounding ,1/2 submerged log or Sea Land box you encounter.

FAST FRED

[Chuck Bates]

I would be more worried about the bilge pump keeping up with the water pouring into the hole left by the shaft propelled damaged hull :eek: glug glug :!:

[Navaldesign]

We are at the moment on the completion of the project of a 42 ft sportfisherman. Two different boats will be built: an amateur one, for which we are planning IPS 370 propulsion, and a pro version of the same with twin Boni www.bonimotorimarini.it diesels model BV8406TSIP rated 400 Hp. Boats should be ready for September. We'll have them tested side by side and publish the results.

[kapnD]

Navaldesign, Isnt that an apples to oranges comparison? The question here concerns the drive system, so for a real comparison, both boats should have the same engine, one with traditional shaft drive and the other with the IPS drive. I'm assuming that Volvo is using an off the shelf powerplant. Volvo is to be applauded for their efforts to break the mold (mould?) on propulsion design. It may not be flawless, but few new products enter the market in their ultimate design. I cant help but recall OMC's abortive outdrive entry some 30 years ago. They sold the crap out of them with no apologies... I'm of the opinion that the low speed manueverability gained with the IPS is well worth some trade offs. If you worry about sinking, it would be easy enough to isolate the drive in a watertight compartment, especially with the use of a jackshaft.

[Navaldesign]

I don't really think so. Boni 400 Hp engine is a well known in Italy engine. It is less thirsty than other comparable engines, and top power of 400 hp is similar to that of the Volvo IPS 500. We will have traditional shafts and props installed on the pro boat since it will have to operate 10 - 12 hours a day, 5 months/year with continous clutchinh/unclutching ,so reliability is of vital importance. IPS still has to prove itself though it presents lots of advantages in terms of installation cost and simplicity. The top power of the two systems is similar so, standing on Volvo's data, we should have better overall performance and lower fuel cost for the IPS. For us, the choice of inboard engine/shaft/prop is a must for the pro vessel and the comparison is for us to get some conclusions on our leasure boat installations.

[tom kane]

I would be more worried about the bilge pump keeping up with the water pouring into the hole left by the shaft propelled damaged hull :eek: glug glug :!:
There should be no need for anyone to worry about going aground or striking an object with a shaft drive boat if it is fitted with a Pivotal Drive,using mass produced parts,and you can do it yourself.You can run the drive as a surface drive or as subsurface drive and include pop-pods,kort nozzles,tunnels ect.,Everything can be soft rubber mounted and many other advantages.There are some Pivotal Drive and CAM.A.PROPULSION images in the Propulsion section.

[River Rat]

Well, I know two things for sure about this new outdrive, I wouldnt run it in 2 foot of water like my Carolina Skiffs, and also, wouldnt want to get a crab pot between those counter-rotating wheels! :D

[tom kane]

Perhaps this drive would suit you better.Contra-rotating twin props on a single shaft that can be run horizontal or lowered down 20 degrees and run in a lower gear.Two piece rudder with trim tabs and air lubricated from intergrated exhaust.Motor right at the back or amid-ships.Diesel,LNG,LPG or gasoline with a safe fuel storage and reticulation system.Full Electronic Engine Management System and propulsion safety control,or a carburettor gasoline motor with a safe fuel system.Many more options.

[Danielsan]

Does this exist? as I wanted to design such a construction? any documents about this?

[FAST FRED]

Remember the Volvo is only a setup to replace an outboard or perhaps an I/O .

The designed life is 100 hours a year . 1000 hours to scrap.

Not a realistic choice for a vessel that is cruised more.

FAST FRED

[gonzo]

Fast Fred: you keep on making unfounded claims. A Volvo Penta diesel has more than 1000 hrs of life. I understand there are products you don't like, but how about sticking to facts?

[tom kane]

Danielson.It does exist in a variety of forms.I know of many people working this concept and I have fitted a single shaft with two contra-rotating props on a 5 meter boat with a similar single prop drive to the one in the image on this page,to see just how much extra drag is created by adding an extra prop and I was not excited,especially as other methods meant less machanical power losses to achieve similar effect and results.But work still goes on.None of the people involved would make their work results available.The cost of Patent Search and checking how patent claims relating to such a drive to be put into production for sale to the public is big money,even knowing the patent numbers and unpublished patent applications are a worry.I have tried multi.gearboxes and they are fasinating in a boat with a drive that can be run at different depths and antomatic boxes even more so.You may be able to come up with a new and novel improvements to improve power losses or some othe aspect.

[Cary]

Keep It Simple

[gonzo]

Tom Kane: usually in inboards 15 degrees is all you can run a shaft. Does the double prop setup allow a bigger angle and is still efficient?

[Danielsan]

The sterndrive Duoprop installations as Volvo and Mercruiser have them, have an improvement in efficiency? would it be less when it runs in a duoprop straight shaft setup?

Gonzo?
What would be an ideal shaft angle? less than 15 deg as with a casale gearbox? or even less maybe combined in a slight tunnel in the hull?

greetings?


PS should I put this in an other thread?

[FAST FRED]

"A Volvo Penta diesel has more than 1000 hrs of life."

Depends , today most engine designers figure service life bases on a certain amount of fuel will go thru the engine , not hours.

An example is the Detroit Diesels , where a 6-71 in a 1200rpm gen set will run 20,000 -30,000 hours ,
BUT the same engine with a blower in a sports fish will usually only run 1000 hours and be shot.

Both will have consumed the about same amount of fuel in their lives.

For anyone ever contemplating a Volvo they should go to the Volvo web site and examine the "conditions" placed on the HP use and hours.

The BIG Volvos are competative as marine propulsion power units EG have a cont duty 24/7 /365 rating.

The outboard or I/O competative Volvos have loads of restrictions , or the service life is SEVERLY reduced , and the unit will be operating OUT of its designed limits.

Fine on a ski boat , MUCH UNGOOD for an ocean vessel.

FAST FRED

[Dave Guilford]

Saw an IPS system under a Regal at the Miami Boat Show. Looked like a pretty solid design. After all, they're the same guys that invented outdrives a million years ago.

[tom kane]

Tom Kane: usually in inboards 15 degrees is all you can run a shaft. Does the double prop setup allow a bigger angle and is still efficient?

You can run a shaft angle from well above horizontal to well below 20 degrees..if you wanted to.Efficiency from horizontal to 15 degrees of shaft angle would be difficult to measure,if there was any..on a particular set up.Many shaft boats run a motor at 10 degrees and 10 degrees spread over twin universals.There are many options,and none need to be complicated.

[tom kane]

The sterndrive Duoprop installations as Volvo and Mercruiser have them, have an improvement in efficiency? would it be less when it runs in a duoprop straight shaft setup?

Gonzo?
What would be an ideal shaft angle? less than 15 deg as with a casale gearbox? or even less maybe combined in a slight tunnel in the hull?

greetings?


PS should I put this in an other thread?

Duo props on a single shaft running on their hubs in S/P mode should beat all.Shaft angle alone,can be misleading there are other considerations.

[Danielsan]

Tom, do you mean dual counter rotating prop on one surface drive drive?

couldn't be that complicated, could be almost same constrution as with straight shaft as I see it.

[tom kane]

Danielson.Just take a look at some of the top surface drives,yes they are complicated and so are many inovations on modern autos but they still achieve better fuel and performance.A simple drive like they run hydroplanes on obviously as yet has no equal for speed for general use.Twin contrarotating props on a single shaft may be acceptable some time in the future.Would you risk financing such a drive.There must be easier ways to make a buck.Drives come and go and are revived again.Image shows a very small tunnel in a hull.

[tom kane]

Saw an IPS system under a Regal at the Miami Boat Show. Looked like a pretty solid design. After all, they're the same guys that invented outdrives a million years ago.

Was it not Jim Wynne who patented the basics of the modern inboard/outboard tilting inovation in 1960.I have the patent No if you want it.

[FAST FRED]

""yes they are complicated and so are many inovations on modern autos but they still achieve better fuel and performance.""

WHAT??? Better??? Your kiddin

I had a second hand 1958 Renault Dauphine that regularly got 50 mpg at 65 mph.

Even had a real heater , unlike the VW of the era.

Where are the "improvements" in milage for all the complexity of the new Hybrids?

Most get LESS than 50mpg on the highway , and need engineers that haven't been born yet to keep them operating.

Throwaways at $25,000 a pop?

The old Dauphine could be kept running with lawnmower tools.

Progress is great , if it ever comes!

FAST FRED

[tom kane]

Do not despair FAST FRED..I am inclined to agree with you..but still working on your thinking.

[jmariner]

Unfortunately, this system would be immpossible for the pacific north west region. The props and drive are simply too vulnerable. I spend silly amounts as it is, maintaining the drives after (even small) debris HITS! The Arneson drive system shoud be further explored for pleasure boat/trawler applications.........and not so ridiculously expensive.

[tom kane]

How would a drive like in post #70 suit those conditions..but with a Kort nozzle or propeller shroud or in a tunnel..single screw.It is possible to have a rugged low cost drive that can be protected from damage,and still be efficient.

[gonzo]

jmariner: have you priced an Arneson? They are not designed for trawlers or slow boats. What do you mean by small debris damaging your drives? Drives, of all major brands, take a lot of abuse.

[cyclops]

Small debri in the Pacific Northwest is a 6" X 30' log.