What Size Prop??

[bubbafowler]

I have a 17.5 ft tri-hull ski boat from the 70's. It has a 120 hp I/O Mercruiser. The motor runs like a top and the top end is fine, but I need a better hole shot. I think I currently have a 17 on the boat, but can anyone tell me what size I need to accomplish this with just this information??

 

[sea trout]

17 sounds right.
you can go down to a 15 and get out the hole quicker! just make sure your not goin over the max rpms for your motor on top end.
you should be fine with a 15, but pay att to rpm's.
do u got alum or stainless on there now??

 

[Twenty five ought six]

You've got a heavy boat, and heavy motor -- I wouldn't expect too much in the way of hole shot.

I'm not sure what the emphasis is on hole shot anyway, as it comes at the expense of top end. If it gets up on plane and rides well, I wouldn't worry about it.

 

[bubbafowler]

gotta have a better hole shot to make it easier to ski and knee board and wake board and tube behind. Top end isnt the big deal, its how quick it will pull up. Makes it easier!! and its a stainless.

 

[sea trout]

try the 15 stainless. it'd b nice if u could find one to try befor u bought it, but i think the 15 stainless would b what yer boat needed to pull watersports.
the 15 aluminum may (probably) flex back to a 16-17 pitch when you take off and put the heavy load on it. wich in turn may do you no good to go down a size switching aluminum

 

[Twenty five ought six]

Sort of 6 o one, half dozen of another, but you can pay a prop shop to cup your current prop. That's like adding another low gear.

 

[sogafishin]

Get you a four blade prop and it will launch great.