SeaArk Forecast 156 2012 boat specs
SeaArk
SeaArk Forecast 156 2012
2012
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VS
SeaArk Forecast 170 C 2005 boat specs
SeaArk
SeaArk Forecast 170 C 2005
2005
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SeaArk Forecast 156 2012 vs SeaArk Forecast 170 C 2005 — Same Brand, Different Boat

The SeaArk Forecast 156 2012 vs SeaArk Forecast 170 C 2005 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.

On paper these two are close siblings in the size department — SeaArk Forecast 156 2012 at 15,5 ft versus SeaArk Forecast 170 C 2005 at 17,0 ft. Weight tells a clearer story for trailering families: the SeaArk Forecast 170 C 2005 tips the scales at 775 lbs — 768 lbs less than the SeaArk Forecast 156 2012 at 7 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.

The power gap is worth calling out. Rated to 75 hp, the SeaArk Forecast 170 C 2005 has a 35-hp advantage over the SeaArk Forecast 156 2012's 40-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load.

Both boats are rated for 4 passengers — a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.

At this size, power-to-weight ratio matters more than outright horsepower. The SeaArk Forecast 156 2012 comes in at 0 lbs per hp versus 10 lbs per hp for the SeaArk Forecast 170 C 2005. The lower the ratio the more explosive the acceleration — meaningful on a short RIB where bursts of speed, quick planing, and agility in surf or tight waterways define the experience.

Bottom line: Performance buyers should lean toward the SeaArk Forecast 170 C 2005 and its 75-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the SeaArk Forecast 156 2012 with its 40-hp rating is the more economical daily driver.
General Boat Info
MakeSeaArk
MakeSeaArk
ModelForecast 156
ModelForecast 170 C
Model Year2012
Model Year2005
Measurements / Dimensions
Beam71 in
Beam71 in. (1.8 m)
Beam - Meters1.8
Beam - Meters1.8
Beam - Inches71
Beam - Inches71
Depth - Detail21 in
Depth - Detail21 in. (.53 m)
Depth - Centimeters53.34
Depth - Centimeters53.34
Depth - Inches21
Depth - Inches21
Weight - Detail700 lbs
Weight - Detail775 lbs. (351.1 kg)
Weight - kg317.51
Weight - kg351.53
Weight - lbs.7
Weight - lbs.775
Width [transom] - DetailBottom: 50 in
Width [transom] - Detail50 in. (1.27 m)
Length - Feet15.5
Length - Feet17
Length overall - Detail15 ft. 6 in
Length overall - Detail17 ft. 0 in. (5.18 m)
Length overall - Meters4.72
Length overall - Meters5.18
Length overall - Inches186
Length overall - Inches204
Height [transom]not available
Height [transom]20 in. (.51 m)
Length - Metersnot available
Length - Meters5.18
Body / Hull
Hull materialAluminum
Hull materialnot available
Hull thickness0.100 in
Hull thickness.100 in. (2.54 mm)
Hull typeModified Vee
Hull typenot available
Engine and Drivetrain
Fuel tank capacity - Detail15 gal
Fuel tank capacity - Detailnot available
Fuel tank capacity - Liters56.78
Fuel tank capacity - Litersnot available
Fuel tank capacity - Gal15
Fuel tank capacity - Galnot available
Fuel typeGas
Fuel typenot available
Drive typeOutboard
Drive typeOutboard
Engine max40 hp
Engine max75 hp (55.9 kw)
Operational Info
Maximum capacitynot available
Maximum capacity985 lbs. (446.8 kg)
Maximum peoplenot available
Maximum people4

SeaArk Forecast 156 2012 vs SeaArk Forecast 170 C 2005 — Common Questions

Which is the larger boat — the SeaArk Forecast 156 2012 or the SeaArk Forecast 170 C 2005?
The SeaArk Forecast 170 C 2005 is the longer of the two at 17,0 feet overall. The SeaArk Forecast 156 2012 comes in at 15,5 feet, making it roughly 1,5 ft shorter — a meaningful difference in deck room and overall on-water presence.
Which is easier to trailer — the SeaArk Forecast 156 2012 or the SeaArk Forecast 170 C 2005?
For trailering, the SeaArk Forecast 156 2012 has the edge at 7 lbs dry weight versus 775 lbs for the SeaArk Forecast 170 C 2005. Add a motor (typically 300–500 lbs for an outboard in this class), gear, and a partial fuel load and the difference grows. Lighter is friendlier on smaller tow vehicles and on fuel economy while hauling.
Which boat can handle a bigger outboard?
The SeaArk Forecast 170 C 2005 is rated to a maximum of 75 hp, giving it the larger power ceiling. The SeaArk Forecast 156 2012 tops out at 40 hp. Keep in mind that maximum ratings are just that — matching the motor to the actual load and usage pattern usually matters more than chasing the ceiling.
How many people can each boat hold?
The SeaArk Forecast 156 2012 is Coast Guard rated for 4 passengers, while the SeaArk Forecast 170 C 2005 is certified for 4. Note that legal capacity and comfortable capacity aren't always the same thing — on a full day out, most experienced boaters aim for about 80% of the rated number to keep things comfortable.
Which boat has the better power-to-weight ratio?
The SeaArk Forecast 156 2012 has a better power-to-weight ratio at 0 lbs per hp compared to 10 lbs per hp for the SeaArk Forecast 170 C 2005. A lower number means quicker acceleration and faster time to plane — the number that actually matters most on short, sporty boats like these.
Do these boats require an oversize trailer permit to tow on US highways?
Both the SeaArk Forecast 156 2012 and SeaArk Forecast 170 C 2005 share an 71 in beam — meaning both sit right at the 8’6" threshold that most US states use for standard-width loads. In most states you can tow at that width without a special permit, but regulations vary. Always check the rules for your state and any states you'll be passing through before your first long haul.
Are the SeaArk Forecast 156 2012 and SeaArk Forecast 170 C 2005 from the same manufacturer?
Yes — both the SeaArk Forecast 156 2012 and the SeaArk Forecast 170 C 2005 are built by SeaArk. That means shared dealer networks, common parts availability, and consistent build quality across the line. The choice between them is essentially a question of how much boat you need, not which brand you trust.