Which 50' coupe with Volvo pod drives best?

In my opinion the Volvo Penta D6-435 IPS600 was a poor choice for any 48ft/50ft boat. The small 6 cylinder engine has no reserve power and highly depends for it's output on a compressor and a turbo charger. In hot climates I have seen boats fitted with the IPS600 struggle to get on the plane and the engine was stuck at 2200rpm simply because of the hot ambient air which lacks sufficient oxygen for an effective fuel mix and affected the engine horsepower output which dropped significantly leading to a severe reduction in the vessel's performance figures. Higher sea water temperatures also affected the performance of the D6-435 IPS600 engine. The small charge air cooler was not able to cool the compressed air being fed to the turbo charger leading to high charge air temperatures resulting in poor and reduced engine output. Nothing was able to solve the problem, not even IPS propellers with a different pitch. The same boat without any modifications would perform as expected in winter months and as soon as the ambient temperature and sea water temperature dropped. The D6-435 IPS600 engines do not have sufficient power and torque to power a 48ft vessel in any and all environmental conditions. In hot summer months expected performance figures were only possible if the weight of the boat was reduced. Williams tenders were removed. Fuel tanks and fresh water tanks were only filled to 50%. No more than 5 to 6 persons were able to be on the boat during cruising. In summer weight was a very critical factor in determining the boat's performance.

The annual service cost for a D6-435 IPS600 is probably more if you factor in the boat hauling charges simply to replace the IPS transmission oil.

I've run A LOT of different pod boats..... probably around 40-50 different yachts/boats with them. I've run everything else too Arneson, jets, stern drives, outboards, shafts, etc. etc.

I have not seen these performance issues with IPS and 90F ambient air temperature is what I've run them in with no performance issues. The motors are made to turn high RPM's just like Yanmars....it doesn't matter if they're mounted in front of a prop, a hamilton jet, or an IPS, cruise rpm is 3100 +/-.

In a twin pod installation they're great. Faster than higher HP engines with shafts, much more fuel efficient, lighter, less physical space......much better dockside handling, slow speed handling and all around. If you're using the boat 50 hours a year at cruise the fuel savings more than makes up for having to haul the boat.

I have not seen any complicated electronics issues with any of them. The electronics have been rock solid from what I've seen.

I've run boats with triple pods, and with most (not all but most) the fuel savings is not nearly enough to outweigh having to maintain a third powerplant.

They perform the same with a dirty bottom as a shaft boat. THEY are more sensitive to growth when it comes to the props and drives and that does have a bigger effect than a shaft boat.

I have run them in medium- moderate seas to somewhat rough and they have performed fine. No issues there either. As for the service in a far place......heck, if you have a computer issue with a Cat C18 in the Bahamas, you're flying a tech in with a laptop too........

while the joystick with bow and stern thruster works well enough for most people, it doesn't react as strongly as the pods can when walking sideways or maneuvering so in strong current can be a little hinders, AND the biggie, they're only good for a few good minutes of laying on them till the hydraulic oil starts overheating.......PODS you can sit there and lay on that joystick all day long with no issues.

Perhaps your hull design was the critical factor and why you had such terrible performance during the summer or engine room ventilation too poor.

I like them over shafts in a lot of twin engine applications.

I can't argue with you on Fairline or Princess with the D9's etc as I haven't seen those numbers. I did provide numbers on boats I'm familiar with and direct comparisons showing the advantages of the pods. I have seen several tests where the same advantages were shown. Even a Meridian 441 picked up significant performance when they switched to pods.

Your whole argument about RPM is just lost on me as I'm not use to any boats running at WOT and only 2400 RPM. I'm use to seeing the same max RPM's on shaft drives as on pods. The examples I showed you had the same. Cummins, the basis for all the Zeus pods, QSB 480's WOT is around 3325 RPM. I gave you one very good example that I've run of MAN's vs. IPS and the RPM was the same on both. I personally wouldn't put the design of the Princess 48 or the Fairline 48 at the top of my list of designs. I also wouldn't choose a 50' boat with D9-500. And you indicated later you felt that was underpowered. So, lets compare properly powered boats. I'll stick to my numbers as provided from real boat tests from the builder and confirmed by me in actual operation on well designed, well performing boats.

Volvo D13 pods redline at 2350 rpm. The D11's don't have a much higher redline. Maybe 2500 rpm. Have a friend with a D4 volvo in his pursuit and it redline's at 3400 rpm. The smaller the engine the higher the red line.

I have thousands of miles run on a 2012 48 Sabre Salon Express that I bring back and fort from Fort Myers to New Buffalo, MI. The layout really (even the master) works well and the hidden third stateroom in wonderful for storage or other guests.

With 600 Cummins mated to Zeus drives she cruises 70% load 28 knots and 38 GPH which I think is incredible for a boat with a 52' loa. She has a rock solid feel in rough stuff and at the right speed never pounds. I'd take a closer look at one of these.

For our purposes running the river back and forth the Zeus makes a lot more sense than ips, for the simple reason if you're dealing with random debris you at least have a skeg deflecting items away from the props.

My choice would choose a Maritimo S51. It does come with Volvo D11 670hp engines, but with shaft drive (which I personally prefer) and not IPS, is a great design, well built, and should do exactly what you want!

http://maritimoamerica.com/model/maritimo-s51/

http://www.***************/wp-content/uploads/2015/09/Maritimo_S48_External_2_1200x800.jpg

I hear what you are saying, there are certain limitations in any pod package, IPS or Zeus. I have found that there is a displacement limit on a 435hp package, about 32,000 lbs. before performance degrades. The performance is still not bad, but noticeable to those who have run similar models in the lower 435 and higher 480hp range. Some may find the difference less noticeable than others, but it is apparent when you are trying to optimize the propulsion package. So my experience, 435hp pods for a 42/44 footer is good, but not so much in the aforementioned 48/50 footer.

Another point that I have seen, is that an underpowered pod installation pushing too big (displacement) boat tends to have a smaller operating band when on plane, and with that comes noticeable switch points, where the boat is on plane in a good way but at a relative high cruise, and tends to fall off-plane too quickly, basically feeling like an on/off switch with a narrow rpm bandwidth .

not that I am aware of?