posted 07-16-2009 05:09 PM ET (US)        

During the course of our correspondence, he told me that someone at BW (presumably Chuck Bennett) indicated that only about a dozen of these boats were built between 1999 and 2000.

Intrigued by this, I sent an email to Chuck to confirm, which he did.

posted 07-18-2009 04:17 AM ET (US)            

quote:

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I can see the desire for sterndrive power in the days before modern 2 stroke and 4 stroke outboards

---

What?

On what planet is a sterndrive considered inferior to "modern 2 stroke and 4 stroke outboards?"

Let's see, my 5.7L sterndrive produces more power, gets better fuel economy, is user-serviceable, and costs thousands less than any equivalent outboard in production today.

Please. I'll put my small-block V8 up against any outboard engine.

posted 07-18-2009 06:52 AM ET (US)            

I agree with you.

The fact that my boat lives in a salt water environment and not on a trailer keeps me away. The idea that I can tilt my engines clear out of the water (except for an inch of the transom bracket) keeps me an outboard man.

However, something I hadn't thought of, I'm curious to know how the new 4 stroke outboards compare to IO's for fuel economy.

Norm

posted 07-19-2009 01:16 AM ET (US)            

http://i22.photobucket.com/albums/b309/elaelap/Strike3saltmaiden003.jpg

Tony

posted 07-19-2009 02:29 PM ET (US)         

Sterndrives have the edge in several areas:
-Lower purchase cost
-Lower fuel consumption
-Higher speeds
-User serviceable (I assume David is referring to the 5.7L engine, which is based on a very common GM block)
-Ability to tap into cooling system to provide heat, like on a car
-Easier to fish around

Outboards have the edge in different areas:
-Safety, whether this is perceived or actual I do not totally know. Less of an advantage with Diesel sterndrive power.
-Weight, even heavy, modern outboards weigh less than sterndrives
-Saltwater use since the outboard can be tilted clear of the water
-Winterization. Outboards are self draining so they can be used all winter without concern of damage from freezing.
-Cockpit space

posted 07-19-2009 10:51 PM ET (US)            

The cockpit was large enough to accomodate 10 people at last year's North Channel rendezvous.

I can easily get 6-8 mpg when cruising. With a 125 gallon tank this makes my range more than 600 miles.

The outboard-powered Conquest 23's required lead ballast to make them sit level in the water. This isn't necessary with the IO-powered model; my boat sits perfectly level in the water, and will plane at 14mph.

No, you can't tilt the outdrive all the way out of the water, and that has been a problem for the Bravo III in salt water. My boat is stored on the trailer so I haven't had an issue with this, and I don't boat in salt water.

I would never attempt to work on my own outdrive (apart from lube changes), but I can service nearly anything on the engine. And I do. The only thing I've had to repair in 10 seasons has been a thermostat.

If the boat were swamped, I doubt the entire engine (or more importantly, the carburetor) would be below the level of water. This boat has 3' of freeboard.

posted 07-21-2009 02:21 PM ET (US)            

I/O engines are popular on the freshwater Great Lakes, but fairly unpopular in saltwater environments - so their dispersion is somewhat limited (or influenced) by geography. In the Great Lakes, I/O power is far more prevalent on a 23-27 ft boat than any other format, except perhaps wind.

I've seen Dave's 23 Conquest, and been aboard - I also pulled the cover to take a peek at the powerplant and was impressed that Whaler managed to minimize the lost cockpit space - you hardly know it's there, except for the missing open view of an outboard powerhead back there.

I will argue with Dave, however, on the swamped situation. With 3' gunwales, that only exacerbates the problem by allowing more water to be retained inside the boat and flood the motor. I believe, however, that if you are in a sea state that would flood the 23' Conquest cockpit, you generally shouldn't have gone out in the first place!

posted 07-21-2009 02:39 PM ET (US)            

Even if your Scarab hull was even remotely similar to the Conquest hull, (which it isn't obviously) how was the engine carbureted, what lower were you running, how about prop pitch, and how many props?

The only similarity you have demonstrated is they are both boats.

I have no reason to claim numbers higher than I can actually achieve.

posted 07-21-2009 03:56 PM ET (US)            

I do not find it hard to believe a sterndrive can offer better fuel mileage than an outboard motor or two, that is one of their selling points.

I do, however, find it hard to believe that a boat can achieve two or two and a half times better fuel economy simply by being propelled by a sterndrive.

posted 07-21-2009 04:39 PM ET (US)            

Duoprop is a Volvo trademark, by the way.

Also keep in mind these are big props. The rear prop is 14 inches in diameter, the front is 15 1/4 inches in diameter.

To arrive at my numbers, I fill the tank until the vent spits fuel, then make note of how many gallons it takes to repeat the process when I refill.

Mileage is derived via my Raymarine chartplotter.

posted 07-22-2009 03:59 PM ET (US)            

PS...a small block of say 300hp is a small block of 300hp no matter what it is pushing. At certain rpms it is going to burn roughly the same fuel if pushing a barge or a 13' sport. MPG differs because of speeds and efficiencies. My Scarab is obviously more efficient due to it's top speed compared to yours. I was swinging a Laser 2 14x23" through a 1.5:1 ratio. If you cruise at say 2600rpm at 23mph and I cruise at roughly 33mph how can you get better mpg than me?

The only way without a calibrated flow meter to know your exact mpg at cruise is to run a 3gal tank at cruise until it runs dry. Then you compute how many miles you went and how far on 3 gals. This can still be off due to wind and currents but is a pretty good way to check. The other way is to read a boatload of test reports with similar setups and get a general idea of which boats like yours perform the same way and take an educated guesstimate. For example your boat weighs xlbs, goes 40mph WOT and cruises at 26mph at 3k, etc. Test boat weighs the same, has same power and setup and runs according to what you do, not exact but will be within a couple %. That is how I came up with my mpg numbers on my 115 is because most 115 Suzukis running 4k at 25mph are burning between X & Y so I use that as a guidline and say I burn between say 4-5gph at 25mph which gives me between 5-6mpg at cruise from worse to best case scenerio.

Lastly I highly and knowingly will bet that a 260-320hp 5.7L engine on a 23' boat can and will not get better mpg than my 19' boat with a modern 115 4 stroke that probably comes in half the weight than you.

posted 07-22-2009 06:35 PM ET (US)            

After 10 seasons with this boat, I'm pretty confident in my findings.

posted 07-23-2009 11:52 AM ET (US)            

The engine tests were interesting, but my engine was not listed. Mine is not a 350 MAG or MPI, for whatever that's worth.

I was actually trying to be polite, I'm sorry you took that as acting "that way."

I'm not quite sure why it's so important to you to right some perceived wrong, but you really shouldn't worry about me or what I believe.

posted 07-23-2009 12:35 PM ET (US)            

There is also no question that the Bravo III (and its inspiration, the Volvo DuoProp) is a more efficient drive.

But these improvements are marginal, not improvements of orders of magnitude. Volvo claims the DuoProp will improve fuel economy by 10-12 percent. Make no mistake, a 10 percent improvement is a BIG deal.

But to hear a report of a boat miraculously achieving fuel mileage that is two or two and a half times what it considered normal naturally leads to some skepticism.

A Conquest 23 with an outboard might be expected to achieve 3 MPG. So when David claims he "I...can easily get 6-8 mpg when cruising..." I find that, quite literally, incredible.

The Conquest 23 is close to the size of my own boat. I am not unhappy to get 2.3 MPG with my old outboards. I suspect that with a modern single outboard I *might* be able to achieve 3 MPG. If I thought I could install a motor that would allow it to achieve 6 MPG, I would make the conversion tomorrow...and do a lot more boating.

Measuring fuel mileage by noting how much fuel is consumed over the course a trip of a known length is a perfectly acceptable method of calculating mileage, in fact it is the BEST way to do so as it is measuring the very thing you want to know about, and is not a calculation based of data that may, or may not be, accurate, such as the low fuel flow rate as measured by a fuel flow meter and a speedometer, even if it is a GPS.

I also believe David is in no way trying to deceive us, and is being perfectly honest in reporting the data he has accumulated. But I do suspect that data is profoundly flawed.

posted 07-23-2009 12:53 PM ET (US)            

FYI- a MPI would be more efficient than a carb. With a carbed plant what hp are you 260, 270, or 300?

posted 07-23-2009 02:56 PM ET (US)            

My chartplotter (connected to a Ray 125 GPS) records miles travelled either as a Track or Log. I use the Track feature.

The engine is a 5.7L EFI. It uses a two-barrel carb with throttle-body injection. It is rated at 260HP.

Coincidentally, I'm installing a Flo-scan fuel flow meter in the coming weeks.

I'm off to Rhode Island for the weekend.

posted 07-25-2009 11:00 AM ET (US)            

I wonder if BW designed the 23 initially with an I/O in mind because the static trim is pretty good with the weight of an I/O in the back. And the power trim plus tabs gives a good range of attack angles for all seas when running.

Couldn't tell you about MPG because frankly it sips the stuff and other than on a longish run I hardly bother looking.

posted 07-26-2009 09:37 PM ET (US)            

I'd like to see pictures of your engine compartment, though. If I ever had the money, I would repower with diesel, but I don't think most modern diesels would fit in there.

posted 07-28-2009 08:22 AM ET (US)            

It's tight in the engine bay and although it should be easier to self-maintain, it's so difficult to get your hands in the right places I also get a mechanic save for the simplest jobs.

posted 02-26-2010 10:00 PM ET (US)            

I own a 1997 conquest what was purchased in 98. People actually wonder if my whaler came with the yamaha thats on it. Its a ox66 225 single efi. Its original and still runs great!

This might have been one of the last original whalers. It was the last whaler that the dealer in my area sold. (he stopped selling whalers after brunswick bought them)

Anyone else have one?

Tom