Engines.htm - from American Airboat Corporation - Manufacturers of the World's Finest Airboats

20 x 8 ft. Air Ranger powered by a 502 cu. in. Engine - 4 bladed PS prop
Engine and Propeller Comparisons
Pictured AirRanger 2000 has a Chevy 502
Engine Fuel Consumption Max. Power
GM Diesel 396 ci
Chevy 502 ci
Chevy 454 ci
Chevy 350 ci
Lycoming 200 
Lycoming 125		 5 - 7 gal/hr 
7-10 gal/hr 
6 - 9 gal/hr 
5 - 8 gal/hr		 2800 rpm 
5000 rpm 
3800 rpm 
4600 rpm 
2700 rpm 
2700 rpm

General Motors 6.5 L (396 cu.in.) marine diesel is more economical than a Chevy 454 (7.4 L) but it is also 20 lbs. heavier and not quite as powerful and responsive.

502 cu. in. V-8 automotive engine       larger image
reduction drive, 4 blade composite propeller

 How the engines arrive at the boat yard.  These engines come directly from the manufacturer on pallets.  Buyers receive the usual OEM new engine warranty.
  • Snapshot of offloaded V-8 engines
  • The next step is to dyno-tune the engines to optimize performance for the selected prop.
  • LINKS Specification Sheet (printable 3 p. listing)   Applications :   Hunting    Fishing
    Props        More on Chevy 502 Engine
    •
      Contact:  Stan Floyd, CEO
    Let us send you a quote on the boat of your dreams.

    *Prices are based on the last engines we purchased, not on curent market values.  Prices subject to variation.
    American is not in the parts business - prices are provided as a service and at the request of those making decisions about what they want included on their boat.  Once the decisions are made, call for a quote on the total package.
    Torque/rpm charts are available.  The point is that the torque curve can be modified by changing out the cam...
    The 396 cu. in. marine diesel maintains over 350 ft. lbs. of torque from 1700 to 3500 rpm. Peak at 2800. Wt. 987 lbs.
    Diesel fuel consumption:  5 gal/hr at 2000 rpm, 9 gal./hr. at 2800 rpm.  350 weighs 825 lbs.   454 weighs 965 lb.

    Power Shift Propellers - Wide blade adjustable pitch composite - right hand rotation 

    No. blades Diameter Required H.P. List Price Thrust @ 2800
    2  Automotive 72 inches 200 h.p. $Call 520 lbs. est.
    3 78 inches 380 h.p. $Call 580 lbs.
    4 80 inches 450 h.p. $Call 600 lbs.
    6 82 inches 600 h.p. $Call .
    2  Aircraft  70 inches 160 h.p. $Call 450 lbs.

    The sonic barrier is <700 mph under hot humid sea level conditions - Tip speed breaks the sound barrier at 3000 rpm. Prop noise results largely from high tip speed.  The design goal is to achieve high thrust at below 2400 rpm which reduces stress on components, fuel burn, and noise.

    Propeller Thrust Comparison - Power Shift and 2 other brands

    RPM Levels Pounds of  Thrust Generated
    Engine Prop PSP 4B* PSP 3B AP 78-42 Sens 78-42 Sens 78-42 FLA 78-42
    1000 
    1500 
    2000 
    2500 
    3000 
    3500 
    4000 
    4200 
    4400 
    4600    		 500 
    750 
    1000 
    1250 
    1500 
    1750 
    2000 
    2100 
    2200 
    2300    		 60 
    140 
    250 
    400 
    600 
    840 
    1110    		 140 
    220 
    300 
    420 
    580 
    820 
    1000 
    1200    		 0 
    80 
    160 
    290 
    560 
    780 
    1040 
    1160    		 40 
    100 
    180 
    300 
    510 
    740 
    960 
    1130    		 30 
    90 
    160 
    280 
    450 
    590 
    760 
    873 
    987 
    1100    		 30 
    100 
    200 
    340 
    510 
    680 
    950 
    1050 
    1160

    *PSP 4B - PowerShift Propeller  4 blade
    Data Source - Thrust Comparison Test, Orlando Airport, Friday, Mar. 8th 1996, reported in US Airboat magazine

    Updated Sept, 2001