Sea Sprite 180 - Need more low end acceleration

[badMonkey]

Specs:

Boat: 18' Sea Sprite
Issue: Having problems with low end "hole shots" with 4-5 passengers, I just can't get enough power while pulling larger skiiers out of the water ( 210 lb )
Prop Manufacturer: unsure, but I believe original Mercruiser
Prop Diameter and pitch: 13 3/4", 21P
WOT: 4 people and gear, 40 mph 4900 rpm ( 4400-4800 is operating range )
2 people light gear, 45 mph 4900 rpm
Engine: 4.3LX mercruiser, engine was replaced within last 3 years, been told it is 160HP but I think references suggest 152HP
Boat Make / Model: Sea Sprite 180, 1997 ( i think year is correct)
Boat Length / Weight: 18', no idea on weight and can't find reference on web
Hull is a deep V ( if I understand what that is )

I live in Nebraska and the puddles we run in are generally measured in acres not in miles. Pushing my boat to WOT and to maximum speed is an exercise of faith that I won't run out of water. That said we have a big time on our puddles and I couldn't be happier with my little Sea Sprite.

The problem I am trying to solve is that I am a big guy ( 250lbs and my #2 son is a big boy (210lbs, 6'1"). With 3 in the boat, pulling him out the water is pretty difficult and from my perspective we could gain a lot if I could get to speed more quickly.

I would happily give up 5 mph off of the top end to get some better pulling power out of the hole. 40 mph on our lakes is suicide ( not that the PWC folks have figured that out ).

A friend of mine ( much better with boats ) suggested I go to a stainless 19" pitch prop, 3 blade.

Anyone have different thoughts on that?

Pic of the prop:

Pic of the model #:

 

[steelespike]

Re: Sea Sprite 180 - Need more low end acceleration

From your description I would go with a 21 same pitch in a 4 blade possibly a Solas Amita They seem to produce predictable results If you want a little more jump
maybe 20 or a 19.A 4 blade will handle better at the dock,plane much easier,stay on plane with less power.With the 19 your for sure going to have to watch your max rpm.
Stainlless might do a little better but be more difficult to select the right one
and imo to expensive for the results.

 

[badMonkey]

Re: Sea Sprite 180 - Need more low end acceleration

I went with a 19" - 4 Blade with the expectation of switching back to my 21" - 3 Blade if i get on bigger water where top end speed becomes important. The blade manufacturer is Solas Amina.

This change is pretty substantial and my low end torque (or at least power) is substantially magnified. My 18' Sea Sprite seems to nearly jump up to plane.

For the #s guys WOT = 40 mph with a medium load ( 3 people ), 5050 rpms. This is 250 rpms into red line. On the lake we frequent this is actually somewhat difficult to get to without running out of room ( and porpoising ).

Here is a poorly angled picture: