KEY POINTS:
It was a basic rule of life in Ancient Greece: you didn't mess with the gods. Not only were they unbelievably powerful, they could do things ordinary mortals could not.
Which explains, perhaps, why CMD (Cummins Mercruiser Diesel) named their new drive system after the king of the Greek gods, Zeus.
Not only does the Zeus drive appear to be considerably more powerful than conventional drive systems, it most definitely can do things others cannot.
Until, very recently, it was a truism of the marine industry: if you wanted to sell a 12m-plus power boat in any sort of numbers, you had to fit conventional drives. While there would always be some who were willing to run with stern drives (and a few others who would try other options such as jets and surface drives), the majority always felt more comfortable with conventional shaft drives.
Of course, there have been exceptions: the Genesis range of sports cruisers has long been almost exclusively stern driven _ and very successfully so. However, they have been just that: a glaring exception.
It is, therefore, somewhat of a surprise to find an importer of a new luxury sports cruiser (and a 15m one at that) boldly stating he doesn't expect any demand for the shaft-driven version of his boat.
Noel McKenzie, of Laurie Collins Marine, has been around the waterfront for long enough to have a pretty good idea of what is going to sell and what is going to languish on his marinas. He believes the Doral range of sports cruisers falls firmly into the first category.
Not only do they have a sleek "go fast" appearance, they are also well-appointed and, perhaps most importantly, are fitted with these new Zeus drives. Or, to be more accurate, they can be fitted with Zeus drives; on Doral's flagship Alegria, options also include Volvo IPS or shaft drives.
After several months marketing the new range, McKenzie says he cannot see himself bringing in a shaft drive version.
So what it is about these "Olympian" drive systems that make them so special? Basically, Zeus is a pod system, similar in many ways to Volvo's IPS drive. Both consist of diesel engines matched to drive pods, positioned just for'ard of the transom.
The major difference is that, whereas IPS drives have the propellers facing for'ard, on the Zeus they face aft. Zeus drives are also designed to be placed in hull tunnels with only the skeg and bottom half of the propellers exposed (great in case of a mishap).
Just as importantly, in twin drive installations, the two pods are able to turn independently of each other, with huge impact on high-speed handling and low-rev manoeuvring.
It doesn't take much to see why McKenzie is so sold on the benefits of this new drive system.
A 15m Doral Alegria with a pair of 500hp Cummins 8.3 litre engines through conventional shafts delivers a top speed of around 27.5 knots. Throw away the convention and fit a pair of CMD Zeus drives instead and watch the speedo climb another 8 knots _ an increase of almost 30 per cent.
Then do the same with the fuel consumption ratios: shaft drive: 0.54nmpg/50.7gph @ 27.5 knots versus a maximum of 0.72nmpg/51.1 gph @ 3440 rpm with Zeus.
Best cruise for the Zeus is around 26.5 knots @ 2750 rpm for 30.3gph/0.88nmpg, while the shaft drive has the sweet spot at 14.1 knots @ 1750rpm for 18.1gph/0.78nmpg.
Running the shaft boat at the same speed as the Zeus (26.5 knots), fuel consumption is nearly 36 gph @ 2250 rpm for 0.65 nmpg.
Acceleration is also quicker throughout the range with Zeus, especially from an idling start. And that's not all.
It is the incredibly precise control that the Zeus offers that really delivers the "wow" factor. With CMD Zeus drives hanging under the transom, the 15m Alegria performs like a small runabout. Actually, it performs better than a small runabout _ especially when it comes to berthing and slow speed control.
Apprehensive when slotting a big boat into a tight marina berth on a blustery day? You probably won't be after a few plays with these Zeus drives. Instead, using the joystick control, the boat will be simply "walked" down the narrow fairway and into the berth or sideways alongside the dock.
And then there is the Skyhook "electronic anchor" option. This is like having a direct connection between your boat and Zeus (the original one) way up above, without all of those messy rituals. Instead, thanks to the interface between the Zeus drives and the Alegria's GPS, simply stop where you want, turn on Skyhook and the twin Zeus pods will hold the boat virtually right on the spot, regardless of wind or current.
Of course, there's much more to the Doral Alegria than just its Zeus drives, but I've just about run out of space, so here is a quick summary: Doral is a Canadian company with a 35-year history and Doral boats are available in more than 25 countries. The Alegria is the largest of a nine-model range of sports cruisers.
The cockpit layout combines facilities for comfortable cruising and serious entertaining. Although there are far, far more drink and bottle holders than there are rod holders (there are none), there are concessions for those who like to fish: a big boarding platform and built-in wet lockers for the bait and catch.
There is a wet bar, complete with sink unit, barbecue and fridge/freezer; a lounger more than 3m long; varnished cherry timber; a Raymarine E120 nav system; a collapsible ladder to the foredeck; twin, completely private double cabins and quite a lot more. Oh, and those Zeus drives. Did I mention those?
For a full review of the Doral Alegria and its CMD Zeus drive system, see the March/April issue of Pacific Motoryacht, on sale now.
Any queries regarding Weekend Marine, contact marine editor Mike Rose on (09) 483-8284; (021) 735-015 or email: mrpr@xtra.co.nz
