Pontoon Boat & Deck Boat Forum

I'm curious what top speeds others are getting with 24' pontoons and tritoons with 115 hp. 22mph gps is my top speed with my Mercury 115 with factory prop . I haven't hooked up my tachometer yet so I don't know my rpms. Just wondering if anyone is doing much better with a 24'. I may upgrade to a larger motor in the future but want to see what I can get out of the 115 first since it would most likely be better on fuel. I added a 3rd toon which didn't really improve top speed but did improve the ride and blow out tremendously. I still need to underskin and add lifting strakes.

Ran 25 gps with my Southbay . 27 with underskinning on a perfect day. Twin tube , 24' , 115 4 stroke , 4 blade spitfire prop.

smoker62 wrote:Ran 25 gps with my Southbay . 27 with underskinning on a perfect day. Twin tube , 24' , 115 4 stroke , 4 blade spitfire prop.

27 is very respectable for a 24 foot boat with a 115. Is the spitfire prop stainless steel?

No, just a 4 blade aluminum. Much better than the stock 3 blade black max though. No blowout in tight turns, better top speed and pulling power.

24' pontoon, no lifting strakes, no underskinning.
115hp Yamaha 4-stroke with stainless 14x13 cupped prop. WOT is 5700 rpm.
With a light load I can run 25 mph (GPS).

I still need to underskin and add lifting strakes.

That will help..............but be careful with the strakes, they aren't just angles welded to the sides. and aluminum , especially the thin stuff pontoon logs are made of don't fare well with a lot of heat concentrated in one spot. A Good aluminum welder will know that.

28mph with two tubes and 4 adults, factory 3 blade prop. No strake but the toons have a hull shaped bottom which allows them to plane. Does anyone think my performance would better with a 4 blade spitfire? Right now I have no cavitation problems at all. Trying to figure out what I would gain for the extra expense.

I have found a good welder to weld the strakes on and I've been looking at other boats with strakes to get ideas. I'm just not sure where to get the metal. Does anyone know where to get pre-made strakes or do most people buy the metal and get it bent?

Kramfam wrote:28mph with two tubes and 4 adults, factory 3 blade prop. No strake but the toons have a hull shaped bottom which allows them to plane. Does anyone think my performance would better with a 4 blade spitfire? Right now I have no cavitation problems at all. Trying to figure out what I would gain for the extra expense.

I'd say probably not, unless your slip numbers are in excess of 30% with your current prop. It all depends on your current prop, Rpms, and speed to figure out how efficient it is.

Luke wrote:I have found a good welder to weld the strakes on and I've been looking at other boats with strakes to get ideas. I'm just not sure where to get the metal. Does anyone know where to get pre-made strakes or do most people buy the metal and get it bent?

This place is out of Springfield, Ohio;
http://www.custompontoonboatkitsetc.com/index.html

A local metal supplier can certainly sell you 4'x8' sheets, shear them, and them bend them to your specs with a sheet metal break. You will just need to provide the design. They would be in 8' sections, but I doubt the welder would care.

SW240DF (25' 8") 115 Yamaha. was getting 27.3 MPH. After adding 2 Bimini tops (With two always open) and adding motor shaft extension now 22 MPH. Two 27" tubes not cleaned from last year. Do still get occasional blow out.

What thickness aluminum is usually used for the strakes?

Luke wrote:What thickness aluminum is usually used for the strakes?

If my memory serves me, 1/8 inch. This is from me researching doing it myself over the winter. I never did the project, so I am watching yours. I am sure others could measure the ones on there boats.

1 person, does not seem to matter on fuel amount. Slight wind. 25-26 GPS verified. Aluminum 14x13 Hustler Prop. The boat is under-skinned.

24' tritoon.

7,500 foot elevation with a 12 pitch: 22 MPH
5,500 foot elevation with a 15 pitch: 24 MPH

I COULD run a 14" pitch at 7,500 feet, but my stainless is a 12 so I can also use it at 10,000 feet. Elevation really makes a difference. At 10,000 feet, my 115 only puts out 84 HP.