Propeller Size?

[runnin'skinny]

Hello,
    This is my first post on the site & thats because I am the proud new owner of an 84' 170 & a 93' yamaha 115 2 stroke. Currently the engine has a three blade 17" pitch prop and its so beat up all I can say is it is around 13" diameter. I also have cmc jack plate; I took the boat out yesterday to see how she ran. To my suprise after trimming and jacking the motor to what seemed to be the best position at WOT I was running over 6k (tach only goes to 6K) @ 41mph. Then I put the jackplate all the way down & trimmed the motor almost all the way down @ WOT I still got 5900. I am thinking of going to a four blade 19" or 20" 13 3/4" diameter prop. does anyone have anything similar on there boat that could give me some advice?

[RickK]

Welcome aboard runnin'skinny  :!:  :!:
You'll like the 170 - easy to handle and as you've found out, quite nimble.  We have hundreds of members with 170's so they can't all be mistaken.  8)

[Aswaff400]

i think a 4-blade may be a little too much prop for a 17 ft'r, IMO, i'd go with a 3 blade that's 2" higher pitch, with more rake and cup then what your running now...