I have a 13.5X15 prop and 14X13.
The 13.5X15 runs at 4,800 rpm WOT and boat travels 34 mph.
The 14X13 runs 5,600 WOT and travels 33 mph.
What's best for the engine and suggestions to improve mph (not that 33 is bad).
09-14-2013 11:08 - edited 09-14-2013 11:10
What are the models and the part numbers of each prop.
For best results, if you are looking for top speed a Viper series that will allow the motor to turn about 5100 rpm would be ideal. This is assuming that you have the 3 cylinder 90hp.
There are now 2 different 90hp versions, what is your model number or does your motor have 3 or 4 cylinders?
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The factory recommends that a properly trained technician service your Johnson or Evinrude outboard motor. Should you elect to perform repairs yourself, use caution, common sense, and observe safety procedures in the vicinity of flammable liquids, around moving parts, near high-temperature components, and working with electrical or ignition systems.
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