what pitch prop 3 vs 4 blade

[backyardracer]

let me start over sorry for my mess
ok i have a 2.5L 120hp mercuiser with a 15inX17p 3 blade aluminum prop it is reving a little hard at 4800rpm and about 35mph its on a 16ft tri hull fiberglass boat i dont know exact weight but i think its close to 2500lb fully loaded its not really a very big boat. the prop it came with is beat up pretty badly so i need to replace my ? is should i go with a 4 bladed prop or 3 bladed prop and what pitch any help would be nice
max rpm's on motor says 3900-4300 if i left any thing out just yell at me

 

[junior1113]

Re: what pitch prop 3 vs 4 blade

21" 3 blade 19" 4 blade will put rpms in upper limits of recomended wot rpm range. 4 blade better hole, shots slower planning speeds, and better accel better fuel eff.