Kona Kai Notes


The speeds listed below are approximate and not guaranteed. They are based on the listed displacement and may vary if displacement (weight) varies. All speeds assume well-faired hulls driving through properly sized propellers with suitable gearing to match the power and torque curves of the engine in question. All speeds are in knots per hour. To convert to miles per hour, divide by .87. Horsepower is given as constant 24-hour rated SHAFT HORSEPOWER (SHP); NOT brake horsepower (BHP), nor intermittent ratings. If only BHP is known, multiply this figure by .70 for approximate constant SHP. Figures assume S.A.E. methods. If ratings given in D.I.N., these will be about 8% less than S.A.E. If ratings given in KW, this will give ratings about 75% of BHP (S.A.E.) ratings. In all cases, it makes no difference if the engine is diesel or gasoline powered.

24' 6" x 20' x 5110 lbs. (2.28 tons)
45 shp 14 knots
62 shp 15.5 knots
80 shp 18 knots
125 shp 22.5 knots
180 shp 27 knots
250 shp 31 knots
320 shp 35.5 knots
400 shp 40 knots
500 shp 44.5 knots

Outboard Motorwell option, description from plans

  • Use twin motors only, at least 50 hp each. See Sheet 2 of 5 for transom cut-out.
  • Build up transom thickness to suit motor clamps. (See motor manual)
  • Inboard motor stringers may be omitted, but not 2" x 4" vertical uprights on transom.
  • Span forward 3/8" PW bulkhead to aft side of side frame members under sole.
  • Make motorwell watertight with respect to bilge spaces & self-draining via drain holes through transom.
  • Adhere to motor installation specifications supplied by motor manufacturer.