IPS who likes them ??

ips probably yes

in my limited experience with the units i find the tech's a bit vague as to problem solving and the electronics need more fail safes but on the performance they seem very much on the money. these units lift (not push) a 12t cat to 35kt in under 10 seconds (ips 500,s 375hp rated)

 

sorry only half answered

we tried three prop sizes and stuck with the first ones #3,s we are happy with the results. however we may be back to the boatbuilders /designers/etc
if not maybe gonzo could be a witness for the defence?

 

The gist I am hearing is you dont really want to take one more then a cab ride from a large dealer/internet otherwise you might be doing less boating than you thought waiting for some little gizmo that stops you from getting full power or any.

Heard a good one with a steyr the other day engine wont start, dealer plugs in computer and it says everything is perfect just like the other engine but wont start?

 

Powerboat,

I think this is true of any modern celtronically controlled engine. The IPS system may be having some growing pains, but the complexity of even a normal engine is now so high that repairs can almost only be carried out by a service tech with computer in hand.

I have never used an IPS, but I have kept up with them. While horror stories do happen I know of at least one boat in Florida that sheared off the entire port drive after hitting a submerged shipping container. Aparently the system is designed to fail safely, and the failure while taking the drive didn't allow for water intrusion. The boat limped into port and in 3 days had a new pod installed. I guess it is possible that a standard configuration might have had less damage, but I have also heard of boats pulling the shaft from a collision like this.

Personally I think if I was headed down island to parts unknown, I might prefer a standard system, but for the vast majority of boats, and boaters I am not sure it is really a concern.

 

Hitting a submerged shipping container at speed with a conventional inclined shaft system will in 99% of the cases result in a really, REALLY, bad day.
Epirb, inflatable and PFD's will be put to good use.

Karl

 

Talked to a delivery skipper the other day who hit something with 2 IPS's and they failed to shear off, mangled the housings and sank the boat without damaging the fibreglass??

 

To think i was a little worried about the glassing schedual that Volvo supplied !!
The boats we are making here in China the engine room is a water tight compartment which i thought was a excellent idea !!!With the weight of all thats in there and the water it could still go turtle i would say but the thought is there thats the main thing !!

 

Why needing these over priced, over engineered, electronic dependent, flimsy aluminum casting for nothing? For boat which will run 4 days on a year in the majority?
It is just a marketing crap, giving pompous importance were it is absolutely not necessary, but in the only market were suckers with money are numerous, and so call boat builder installer can have an attitude.
Its all that, a nebulous of thin air, and extremely dangerous. I know that by experience.
It is the least satisfactory system in the long run, and the lost of efficiency is phenomenal. But it's new, come from Volvo, and sold to loaded suckers.
When the yachting go wrong, it goes all the way, and I think Volvo topped them all.
Engine, tranny, shaft, screw, rudder = The best efficiency, the safest record, easy and cheap to maintain and repair.
But it's no good enough for suckers, and all the middle people don't get the same profit.

Lister

 

Can anyone share specific performance test data from identical boats fitted with inboards, sterndrives, and IPS?

http://www.volvopenta.com/VOLVOPENT...A_IPS/FORWARD FACING/PAGES/CRUISINGRANGE.ASPX

Would also like a link to each specific boat if anyone has it.

 

I am sorry, but this is just a text, a marketing text.
These numbers are irrealistics. For glossy brochures.
Don't beleive one word.
Lister

 

40% longer cruising range
• 20% higher top-speed
• 30% reduced fuel consumption
• 50% lower perceived noise level

A huge impossibility.
The consumption is what the engine use, 0.2g. per hp and that nothing will change. At best 0.18g.
Why they don't say 400% more range They realy think we are all *****?
The speed is the same as a straight shaft. the location of the engine system is not at its best with the Volvo system. A lot of new model hull need more volume aft, making the low speed a deadly proposition for the consumption and the viability of the engine.
It is the sea, not an highway, full speed by force five is impossible in normal condition. (no racing crew)
The noise level as nothing to do with the propulsion.

Overprice, over the top marketing stunt and flimsy aluminum casting.

Lister

 

Please post test data if anyone can share or has a link to real-world test data comparing the same hull with IPS vs. inboard or vs. sterndrive. And please identify which boat the test was done on. A guess is the 41 and 52 above are regal hulls but I can't find that information on the volvo or regal sites.

 

Cheap and simple and low maintenance yes BUT best efficiency
what are you measuring?

 

See http://www.sabreyachts.com/motor_yachts/sabre54_express/performance.php

Sabre 54'. Test results by the OE, one boat with IPS one with CAT in-boards:

Looking at the test data you will find that with 23% more hp the inboard boat had a 7% lower top speed and at a 25 knot cruise it consumed 40% more fuel yielding 25% less range even though it had 14% more fuel capacity.
In this particular boat that is almost better than what Volvo claims in their marketing.

And, if you study the test data it appears that the IPS powered boat was run with a heavier load onboard.

All of this would not be possible without huge efficiency gains in the propulsion system itself. It has nothing to do with the engine or engine brand. Suggesting that it has to do with the Volvo engine being more efficient than the CAT = BS.

B.T.W: "Flimsy Aluminum Casting" - What are you talking about ? Both Volvo and Zeus use Bronze or SS in all underwater gear.

Karl

 

I'm not aware of any IO boat that has been converted to use IPS. My guess would be that in the 35' - 40' range (If we are talking lighter, faster) and 20,000 - 28,000 lbs. a duoprop sterndrive would be at least as efficient as any Pod drive. If the boat got heavier and slower the pod (because of more prop in the water) might be more efficient.

As far as IB vs. IPS: I know of two examples that can be viewed as apples-to-apples: The Sabre 54' (Uses to be called 52' but nothing significant has changed). Sabre has on their website test reports on this boat with C15 CAT and IPS.
The other one is the Tiara 3600 Open. They used to build this boat with 425 and 480 hp Cummins IB and now with IPS (offered with 300 and 370 hp IPS). I just looked on their site and they have removed the IB test data. As I recall (But no guarantee) the IPS version with 370 hp was faster than the IB version with 480 hp.

Somewhere in the public domain there is also test data on a 45' Formula; One with IPS something and one with IB (As an IB I think they built this boat with 540 hp Cummins or 575 hp Volvos). Sorry, can't recall where to find it.

Karl