Volvo Penta IPS

some semi solid info on volvo IPS

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...

 

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.

 

"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

 

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 glug glug :!:

 

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.

 

comparison?

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.

 

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.

 

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.

 

Ips

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!

 

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.

 

Straight shaft Counter Rotating props?

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

 

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

 

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?

 

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.

 

Keep It Simple