Does SS make sense for a 25HP Merc on a 14' Starcraft Alum?

[WylieJay]

2000 Starcraft 14S with the same year 25HP mercury Classic 2 Stroke.

I am currently topping out at 23-24 MPH with myself in the boat, looking to squeeze another 1-2 MPH out of her. Currently I am running with a Quicksilver 13P Aluminum 3-Blade prop but entertaining moving to a 14P Stainless Steel prop.

Was having a look at the Solas Prop (1231-100-14). However, within the product information, the following snippet got me a bit confused..

• Offers good acceleration and all-around performance
• Smaller pitch sizes offered in extra large diameter with increased blade area
  [*]Large ear design is ideal for pontoons, commercial hulls and heavy loads

Large Ear Design? How would that play into the equation here?

 

[Frank Acampora]

Re: Does SS make sense for a 25HP Merc on a 14' Starcraft Alum?

The "large ear design" means that each blade has more area than their standard prop in the same diameter. This allows more water to be "moved" with displacement hulls like pontoons and heavy boats or boats carrying heavy loads.

You need to decide if your boat is "heavy" for the size engine (25 horsepower) or if you are carrying a heavy load for your hull. Decide by comparing the maximum horsepower rating of your hull versus what you have and the maximum weight or persons it is rated for vs what you actually carry.

Also decide if the cost of stainless is really worth the extra 1 or 2 MPH you will probably gain and the slight but distinct possibility of damage to your lower unit if you should decide to break rocks with it.

Personally, I only run stainless props (or for my old school engines, Bronze).

 

[fishndirk]

Re: Does SS make sense for a 25HP Merc on a 14' Starcraft Alum?

Sounds to me like 24 mph is a little slow for a 25hp 2 stroke on a 14 foot boat, unless your boat is VERY heavy for its size. My friend runs a 2003 Tohatsu 25hp 2 stroke with a cupped 12p SS prop on a 14 foot boat an he gets 30mph easy on it, even with 2 adults. I run a 14 foot alumacraft with a 2010 Tohatsu 20hp with an 11p prop and get 26mph out of it. I believe the prop you are wondering about is the Solas New Saturn. I have ran this prop and if that's what your talking about be advised this is a very good prop but the blades are very sharp and it has a small exaust flange and is very light in weight compared to other ss props. In other words it is a very fast spinning prop and you would be justified moving up in pitch if you are already at the top end of your rpm range. This will get you a couple more mph but I'm still suprised that you are only getting 24mph as is, especially by yourself.

 

[steelespike]

Re: Does SS make sense for a 25HP Merc on a 14' Starcraft Alum?

Maybe we can fine tune your setup. Is this a bare bones boat. maybe about 200 lbs dry weight?
Is the anti vent plate(just above the prop) about even to an inch above the bottom of the transom.
have you distributed the weight carefully. And adjusted the trim as well?
You should really have a tach to help determine what you may need and to tell if the new prop and rpm are right.
Working backwards with a prop calculator it appears your rpm may be low at about 4900.
The only way to be sure if the rpm is with a tach and gps speed.
Its possible you could make 30 mph if everything is just right.

 

[fishndirk]

Re: Does SS make sense for a 25HP Merc on a 14' Starcraft Alum?

That is true steelspike good call. We definately need all that info to help make a good informed suggestion. Iether the rpms are low or there is an unusually high amount of prop slip going on.

 

[WylieJay]

Re: Does SS make sense for a 25HP Merc on a 14' Starcraft Alum?

Maybe we can fine tune your setup. Is this a bare bones boat. maybe about 200 lbs dry weight?
Is the anti vent plate(just above the prop) about even to an inch above the bottom of the transom.
have you distributed the weight carefully. And adjusted the trim as well?
You should really have a tach to help determine what you may need and to tell if the new prop and rpm are right.
Working backwards with a prop calculator it appears your rpm may be low at about 4900.
The only way to be sure if the rpm is with a tach and gps speed.
Its possible you could make 30 mph if everything is just right.

The boat, without the engine, seats, etc. is 250lbs. - it's a 14 foot v-hull with a 55lb. trolling motor attached to the front (~50lbs), deep cycle battery underneath the front deck (~60lbs). I also typically carry about 50lbs of fishing gear in the boat.. and myself - a whopping 155lbs of fish-catching machinery.

http://boatspecs.iboats.com/Starcraft_Marine__SF_14S__2000/bp/66b87082

I do realize the necessity for a tachometer, so I'll need to get that installed this week.