motor set back on a ponton?

[bav/270w]

I am looking for some input about motor set back.
I Installed a center log on my 1989 20' lowe a couple of years ago. Love the increase in performance. But always looking to tweak a little more out of it. Currently running a 1990 115 evinrude w/ a 133/4 x17 prop. getting 28- 30 mph gps speed. currently my cavitation plate run right off the bottom of the center log app. 1" from log when trimmed all the way down.
My Question? does anyone have thoughts if I were to redesign my transom and raise my engine to give it some set back would I benefit from this. If so, How high can I go if I have say, 30 inches from bottom center tube to prop.

 

[BrianMc]

Re: motor set back on a ponton?

Why not try a jackplate?

 

[5150abf]

Re: motor set back on a ponton?

Long shot but I would see if I could borrow a jack plate, a toon isn't a normal boat and they cavitate pretty easy anyhow and a jack plate would be the easiest cheapest solution, it gives you set back and you can raise the engine and best of all it is bolt on.

If you could borrow one and see what it did it would save you bunch of money if it doesn't work.

I would worry that if you raised the engine much at all it would blow out, the water behind a toon isn't clean like a mono hull boat.

The other thing with any boat is you have to try it to see if it will work, somthing you think for sure will work doesn't and things you don't give a chance work better than you ever thought.

 

[bav/270w]

Re: motor set back on a ponton?

Thanks for the input. Will give it some thought.

 

[Boss Hawg]

Re: motor set back on a ponton?

I have to agree with the others on the jack plate-
I have about the same set up as you- '86 20' Bass Buggy- '87 Johnson 110- 13 3/8 x 17 SS prop & get 30mph from it-
I'd love to add a 3rd log but i'd have to get another trailer also- I have a float on now

 

[Bamaman1]

Re: motor set back on a ponton?

Pontoons are not like bass boats. Numerous people load onto the noses of pontoon boats--thus lifting the rear ends and making the props ventilate. Sometimes, dropping the engines down 1" might solve the problem. It's all trial and error. Sometimes changing the props will also solve the problem.

You don't commonly see jack plates on pontoon boats, as they can put too much stress on marginal transoms. As people get on and off the boat, a manual jack plate would be a hassle to adjust.

Some people install a third toon thinking it's going to improve speed. They primarily make the boat handle heavier loads, and improve ride and seaworthiness. A twin toon with strakes will walk away from a tritoon because they're lighter, and getting the nose cones out of the water is the secret to speed.

Sometimes a boater has to accept the limitations of the boat hull/engine combination.