Aeronca offered a 165 horsepower option in production-the Franklin 6A4-165-B3. The Continental O-300-A of 145 horsepower was also eligible. You might check the approved STC's for the model 15-AC Sedan for later optional engines. If for a seaplane version or floats contemplated, the gross weight would then be 2,100 lbs rather than 2,050 lbs. By the way, there is a 15-AC Sedan for sale at CMA with the C-145, N1204H.