[BOWFISHINGARKANSAS]

I've got a 55 on my 1642 and it does fine..

 

[DB1534]

I got a 70 in mine and its fine

 

[dedi]

Yeah thats what doesnt make since how a smaller boat has a bigger HP rating. The diffrence in some boats may be that its a flat bottom vs a simi v or something idk. My boat is older though. But any advise before i start trying to put my pods on there

Regs below - if you have trouble with formula let me know

NEW BOAT BUILDERS HOME PAGE

Safe Horsepower
Subpart D--Safe Powering
Sec. 183.51 Applicability. This subpart applies to monohull boats less than 20 feet in length, except sailboats, canoes, kayaks, and inflatable boats, that are designed or intended to use one or more outboard motors for propulsion.
Sec. 183.53 Horsepower capacity. The maximum horsepower capacity marked on a boat must not exceed the horsepower capacity determined by the computation method discussed in paragraph (a) of this section, or for certain qualifying boats, the performance test method discussed in paragraph (b) of this section.
(a) The maximum horsepower capacity must be computed as follows:
(1) Compute a factor by multiplying the boat length in feet by the maximum transom width in feet excluding handles and other similar fittings, attachments, and extensions. If the boat does not have a full transom, the transom width is the broadest beam in the aftermost quarter length of the boat.
(2) Locate horsepower capacity corresponding to the factor in Table 183.53.
(3) For a boat with a factor over 52.5, if the horsepower capacity calculated in Table 183.53 is not an exact multiple of 5, it may be raised to the next exact multiple of 5.
(4) For flat bottom hard chine boats with a factor of 52 or less, the horsepower capacity must be reduced by one horsepower capacity increment in Table 183.53.
HORSEPOWER CALCULATIONS FOR OUTBOARD MOTORBOATS
Outboard Horsepower Capacity
Compute the Factor = Boat Length x transom width

If Factor is (to the nearest integer) 0-35 36-39 40-42 43-45 46-52
Horsepower is 3 5 7.5 10 15
Note: For flat bottom hard chine boats, with a factor of 52 or less reduce HP one capacity increment
If the Factor is over 52.5 and the boat has :
Remote Steering and at least 20" Transom Height HP = (2 x Factor) -90
No remote steering or less than 20" transom Height
For flat bottom hard chine boats HP = (0.5 x Factor) -15
For other boats HP = (0.8 x Factor) -25
(b) For boats qualifying under this paragraph, the performance test method described in this paragraph may be used to determine the horsepower capacity.
(1) Qualifying criteria.
(i) Thirteen feet or less in length;
(ii) Remote wheel steering;
(iii) Transom height (A) Minimum 19 inch transom height; or, (B) For boats with at least a 19 inch motorwell height, a minimum 15 inch transom height;
(iv) Maximum persons capacity not over two persons;
(2) Boat preparation.
(i) The boat must be rigged with equipment recommended or provided by the boat and motor manufacturer and tested with the highest horsepower production powerplant for which the boat is to be rated, not to exceed 40 horsepower.
(ii) Standard equipment must be installed in accordance with manufacturers' instructions.
(iii) The lowest ratio (quickest) steering system offered on the boat model being tested must be installed.
(iv) The outboard motor must be fitted with the manufacturer's recommended propeller providing maximum speed.
(v) Standard permanently installed fuel tanks must be no more than one-half full. Boats without permanent tanks must be tested with one full portable tank.
(vi) Portable tanks must be in their designated location or placed as far aft as possible.
(vii) The outboard motor must be placed in the lowest vertical position on the transom or, if mounting instructions are provided with the boat, at the height recommended.
(viii) Boat bottom, motor and propeller must be in new or almost new condition.
Note: The use of the following special equipment should be considered because of the potential for exceeding
the capabilities of the boat while performing the test:
Racing Type Personal

 

[redkodiak20]

I had the same problem. The information I had said 40 HP was max for my boat 1652 Polarcraft but done some more searching and found out it was 40 HP tiller handle and 70 HP remote steer . I will try and find the website it was on.