Outrage Engine Mounting Height; Performance

Optimizing the performance of Boston Whaler boats
KARLOW
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Outrage Engine Mounting Height; Performance

Postby KARLOW » Thu Nov 01, 2018 12:59 am

[An 1982 OUTRAGE of unspecified length powered by a Honda 150-HP Outboard] has an aluminum propeller.

What is the proper engine mounting height?

What is the expected performance?

The hull may be damp.

jimh
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Re: Outrage Engine Mounting Height; Performance

Postby jimh » Thu Nov 01, 2018 5:35 am

KARLOW wrote:What is the expected performance?

Performance will be a function of the total boat weight, the horsepower, and the hull type. To predict performance we must know the total boat weight. A c.1982 OUTRAGE hull is probably either an 18, a 22, or a 24/25-foot model. Clarify the hull model and the total weight in order to get a better estimate of the possible maximum speed.

KARLOW wrote:What is the proper engine mounting height?

The "proper" engine mounting height is the height that works best for the particular combination of the boat, the engine, the propeller, the total boat weight, and the operating conditions, and allows the outboard engine to accelerate to the manufacturer's recommended full-throttle engine speed range, preferably to the upper one-third of that range, when the boat is operated in its normal to heavier-than normal loading with gear, fuel, passengers, and so on. Thus we must have two very important additional data from you:

--what is the manufacturer's recommended engine speed range in RPM for full-throttle operation?

--does your boat have a tachometer that can make accurate measurements of the engine speed in RPM with resolution to at least 100-RPM?

The typical engine mounting height will likely be elevated from the lowest position by at least one-hole-up mounting. Higher mounting may be useful. Much depends on the propeller design. All we know about your propeller is that it is made of aluminum. Clarify the model and dimensions of the propeller to get a better estimate of engine mounting height. Provide accurate data about the following:

Propeller diameter, pitch, make, and model.

Assuming you have an accurate tachometer, then provide accurate data about the present performance of the boat by giving details of engine speed in RPM, engine gear ratio, propeller pitch in inches, and boat speed in MPH. Describe how boat speed was measured. If boat speed is measured as speed-over-ground with a global navigation satellite system device, be certain to mention the device and if any augmentation of precision was used in the position determination. Describe water conditions such as temperature, current, and waves.

jimh
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Re: Outrage Engine Mounting Height; Performance

Postby jimh » Thu Nov 01, 2018 7:09 am

KARLOW wrote:The hull may be damp.

I would not use the description "damp" if you mean to say you suspect that the interior foam core of the hull is saturated with water, and the hull has acquired a significant additional weight due to that entrapped water.

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Phil T
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Re: Outrage Engine Mounting Height; Performance

Postby Phil T » Thu Nov 01, 2018 9:28 am

Without knowing a half-dozen pieces of information, we can't answer the questions.

Here is a great reference chart that may help.

http://continuouswave.com/whaler/reference/performancePrediction.html
1992 Outrage 17
2019 E-TEC 90
2018 LoadRite 18280096VT
Member since 2003

jimh
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Re: Outrage Engine Mounting Height; Performance

Postby jimh » Thu Nov 08, 2018 9:24 am

KARLOW--a week has passed since your initial posting. You have not contributed any of the requested information, even the most simple information such as identifying the length of the boat you are asking about. Are you still interested in this discussion?

[Thread closed after a month with no reply from the initial poster.--jimh]