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 Performance
Ploys by
Cap'n Jack Perdue
It's what boating is all about.
Just listen to most groups at the bar or in the locker room. Chances
are they're talking, proudly or unhappily, about the performance,
or lack of it, of their powerboats.
In fact, in a little survey we did a few years
ago, we were able to determine that the average powerboat owner
is actually driven to terminological inexactitudes (which is a polite
phrase for lying through your teeth) when discussing how fast their
boating rig is capable of going.
Most of us are content to just tack an extra 10
miles per hour onto our top speed in casual conversations, while
a very small minority will go out and purchase a super-fast craft.
If you have sufficient disposable income these days, it's actually
possible to crack the 100 mph mark.
Most mariners are content to make a hobby of increasing
performance, whatever it may be, of their fishing boat, runabout
or cruiser, just to experience the satisfaction of going a few miles
per hour faster with the same hull, same powerplant and same cost
per mile the next time they meet up with friendly competitors on
the lake.
So that's what we'll concentrate on in this chapter,
a common sense approach to performance.
The first thing a skipper thinks of when planning
to maximize performance is the powerplant and, particularly if his
plans run to powerplant replacement, a new and more powerful outboard
motor.
There are specific improvements you can expect
when increasing the horsepower on your transom and, quite frankly,
they're not always that dramatic nor possibly what you expected.
For instance, a 10 percent increase in power on the average boat
will usually result in about two to four percent increase in top
speed, and this is a diminishing increase the faster you go.
Which means that if you're dissatisfied with the
40 mph you get with your 100 horsepower motor, and trade it for
a 140 hp model (for a pretty dollar, I might add), you had better
be prepared to be satisfied with a new 45 mph top speed, give or
take a mile or two. So before you even think about trading up your
engine, here are a few common sense, and often remarkably successful,
alternatives.
If your boat's powered by an outboard motor, it
could be set too low on the transom for maximum efficiency, which
could easily cost you one or two miles per hour at the top end.
If it's mounted too high, then so is the propeller. That's the gadget
that converts the power of your engine into motion. Of all pieces
of equipment, the prop is most likely to affect how fast your boat
is going to travel. And the wrong propeller, or the right one at
the wrong height, or even a damaged or slightly distorted one, can
without doubt cost you up to two or three miles per hour. Or maybe
even more.
Every propeller is a compromise between lugging
power and speed. If it doesn't create sufficient thrust to bring
you cleanly and quickly onto plane, it has too much pitch. If it
pops you out of the hole with power to spare, it likely has too
little pitch and is adversely affecting your top speed.
Perhaps the permanent weight distribution aboard
your boat is not conducive to proper trimming which in turn can
cause loss of speed through plowing. Or maybe you're riding bow
high with the stern never getting fully onto plane. And then there
is your non-permanent load which stealthily grows as the season
waxes. When you launch in early summer, your boat is usually Bristol-fashion
neat and uncluttered, but as more boating weekends pass, all sorts
of things start collecting up under the bow, in lockers or in the
bilge. Pretty soon it's like having an extra passenger leaning over
your shoulder and staring balefully at the speedometer.
There's the obvious possible deterrent to reaching
full throttle if the cables from the remote control are not properly
adjusted for full throw. And if the throttle isn't opening right
to the stop, the prop isn't spinning quite as fast as it should.
And there goes another mile or two.
Now let's take a look at the hull's wetted surface,
akin to where the rubber meets the road.
Any hull anomaly can represent a performance problem.
You probably know the difference between a hook and a rocker, a
wow in your either in or out. These keel aberrations can certainly
affect both a boat's performance and handling qualities. So while
you have yours out of the water next time you find it necessary,
check the bottom with care.
In addition to keel oddities, look particularly
for delamination signs, gelcoat cracking or deep scratches. Remember
that the gelcoat is your waterproof covering that protects everything
within.
Here's something that may surprise you in your
search to wring all possible speed from your rig. You probably assume
that a waxed and polished wetted surface will slide you through
the water a little bit faster. It isn't necessarily so.
Your boat may in fact be slower than if you were
to sand it lengthwise with 600 grit wet sandpaper. It's all a question
of breaking the water free from the hull as it passes through it.
Mind you, it's equally important to prevent algae from growing or
forming on the bottom and slowing you down. A properly applied coat
of anti-fouling paint, of the type recommended for your waters,
will handle both problems nicely.
So you add a bit of speed by adjusting the placement
of your outboard motor and a bit more by choosing a more productive
propeller. Then you find a little extra by reducing superfluous
load and improving weight distribution, then create a final speed
bonus by optimizing the condition for the wetted hull surface. And
you suddenly discover that the fault, dear Bruce, was not in your
powerplant at all, but in yourself for not properly setting up your
boating rig for top performance last spring, then maintaining its
condition throughout the summer.
But don't feel too bad about it. You are a member
of a very large fraternity.
HEADS AND TAILS
A major responsibility you accept as a skipper is to protect the
waters on which you go boating and to ensure that all on board your
boat do likewise. That means that nothing should be thrown over
board.
The Canadian Coast Guard divides your jetsam into
black water, grey water and solids of any kind. Black water is sewage
from your marine toilet. Grey water is the dirty water from your
bilge or the detergent-laced water from your galley or shower, if
you have one.
Jetsam, as opposed to flotsam (which is stuff
that washes overboard inadvertently), also includes plastic wrappers
that can foul your prop, floating cans and other unsightly garbage.
So for goodness sake put all your garbage into a bag and dispose
of it when you return to shore.
The most controversial of the regulations governing
pleasure craft in Canada is, of course, the ban on Porta-Potti types
of marine toilets that are designed to be emptied into toilets on
shore. This portable unit consists of two parts. One is a holding
tank that seals off and can readily be transported without danger
of spillage. It is specifically designed for recreational use in
campers, motorhomes and cruisers. It was used extensively in all
three until the government decided to ban them from all boats in
Canada.
The reason given was they didn't trust boaters
not to empty them overboard when nobody was looking. This decision,
which certainly seems remarkably selective, has cost skippers thousands
of dollars.
Why any boater in his right mind would dump raw
sewage into the lake that he is cruising on, swimming in and fishing
in is quite beyond understanding. But you had better abide by it
or pay a fine. So here is an excerpt from the Canadian Coast Guard's
"Safe Boating Guide."
The following is a list of areas in which boats
are required to have holding tanks and cannot pump sewage overboard:
all waters in Ontario; in Manitoba, the Assiniboine River in the
city of Winnipeg, the Red River and Shoal Lake; in B.C., Shuswap,
Mara and Okanagan lakes.
For other boating waters in Canada the regulations
are unclear. Even the Coast Guard guide mentions that a number of
additional waterways are being considered for restrictions. The
rest of Canada, presumably, requires at least a macerator/chlorinator
but this is not spelled out in the guide.
Skippers of small pleasure craft in Canada have
every right to be indignant when they cruise by a pipe spewing filth
from a local industry or waterway. Or if they see a weir or a dam
on one of their canals frothing at the mouth from detergent being
dumped into the stream.
It has been estimated that one percent of the total
pollution in our waterways comes from pleasure craft, with 10 percent
from cottagers who line the banks. The rest, and by far the largest
amount, comes from industries and farms. But these last major polluters
are virtually above the law, far too strong politically to expect
to be charged unless in extreme cases, such as when people died
in Grassy Narrows in Ontario from by-products of local paper mills.
If you want to know more about that, just drop me a line. (Editor's
note: The author won the Canadian Kortright Magazine Writing Award
for his series on water pollution in Canada.)
It appears that boaters in Ontario, and also those
boating on selected waters in the rest of Canada, must accept a
special role in the fight against water pollution despite that they
represent a very small part of the problem, but must play the government
game. The fact that we regard our lakes and rivers as a recreational
resource rather than a sewer means that we must lead the fight for
cleaner waterways.
So what of the multitude of boats that are too
small, or simply unsuitable, for the installation of a holding tank
system? Skippers should do a little research before a cruise to
locate public toilets in the area and guests should be warned to
"go" before they leave the dock.
And, of course, what you do when swimming from
the boat is strictly between you and the fishes.
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