What to expect from my Motor/Hull combination.

[IamCanadian]

So this is my NEWB Question.

This fall I rescued a 1975 15 ft Cathedral hull Fiberglass Boat It is an EX-EL Acadian. (Doing a Transom and floor on it)

On the Tag it states Max load of 1280 lbs How much this boat weighs I have no idea.
I got this boat for $25.00, No trailer, motor or steering, But it did have an old but working Eagle ID fish finder.
Hull is in GREAT shape, Not a sign of sitting on a beach or dock rash of any kind.

So I found myself with a 25.00 Boat. But it is just too big to paddle around

So Now I need to find a Motor, and a trailer and steering, Even buying old used stuff will add up FAST.

But...Maybe not, Found a Local Ad. With the heading "Desperation Sale" Yippie!!!!!
It was for a 14" FG boat with trailer (Home built but really well built) 50hp 1966 Chrysler In perfect running shape, With new seats and a Single cable steering system.
I went to look at this package and Got it home for the price of 175.00. GOOD DEAL!

The only problem was it is a short shaft motor, I need a long for the Cathedral, But thanks to the power of the internet and iBoats Another member (who has a long but needs a short) And I are trading the needed parts to one another...even more interesting is we received out motors on the same day...or close too.

So I told you this whole big story to ask one simple question.
What kind of speed can I expect from this FG cathedral hull boat with this 50 on it. I can tell you any measurements you want, except actual weight, I will take pics also and post them.

Anyway Hope you liked reading the long version of a short question.

 

[Frank Acampora]

Re: What to expect from my Motor/Hull combination.



When this 15 foot Glastron Deep Vee had a 1969 Chrysler 55 on the transom it topped out at 27 with me alone and two 6 gallon gas tanks. With a couple of people it dropped to 23-24. Waterskiing was possible but deepwatering a slalom ski took skill. Wakeboarding will be easier.

I expect your 15 footer should do similar. I would not expect 30 MPH, but you may get as high as 28-29 if you experiment.

You can try starting with a 10 3/8 X13 1/2 prop but you may find you will need to drop to an 11 1/2 or 12/ 1/2 pitch prop. These are splined thrust pin props described as "pin drive." They were in use on Force engines up until late 1980s to early 1990s. So, they are still relatively easy to find.

Incidentally, your 50 was one of the lightest ever made at about 156 pounds. So, you still have 1124 pounds to spend on people, fuel, battery, and other equipment.

 

[kenmyfam]

Re: What to expect from my Motor/Hull combination.

Just a guess but around the 25mph mark. Everything is dependant on load and set up though.
Good Luck with everything.

 

[eavega]

Re: What to expect from my Motor/Hull combination.

I'll agree that you should be looking at somewhere in the 25-30 MPH range. I had a 15' open bow tri-hull, and with a 50 HP Johnson on the back running a 13P prop (and with smart-tabs) I could get the boat about 30 MPH if I was running downwind. It will be sufficient for tubing, but on my tri-hull even with the 13 P prop the hole shot was awful, so a skier would have to eat a lot of water to get up on plane.

Incidentally, the boat was rated for a 70 HP max. I put a 70 HP on the back of it and was much happier with the overall setup.

Rgds

 

[southkogs]

Re: What to expect from my Motor/Hull combination.

Funny thing about small tri/cathedral-hull boats is that depending on the boat, they can be rated anywhere from 50' to 100' HP. They all seem to live (when powered right) in that 25MPH zone with top ends around 30MPH (good water, no one on board, tail wind, fish pushing from behind, etc.).

My last outboard was a '72 Royal American 15' tri/cathedral-hull. Rated for 100HP and we ran a 65 on it. Topped out at 32MPH (see above conditions), and averaged about 25. It was a great boat to ski behind and propped right could even deep water start a slalom skiier with 3 people on board.

Enjoy!

 

[IamCanadian]

Re: What to expect from my Motor/Hull combination.

Good info!
As it stands right now the motor has a 10.5 pitch prop, After I get it in the water in the spring, I will most likely pick up a 12.5 pitch,
The normal load in the boat will consist of about 480lbs of ppl, My fiance, myself and our 2 girls, Our fishing gear 2x6gal tanks A battery and a 3hp lightwin for trolling,
The only time the 4 of us will not be in the boat is if we are tubing, Or I go fishing on my own in the early morning.....the girls love sleeping in.
This hull is rated for a 50hp, I was pleased to find out how light this motor is, Advertised @ 134lbs.
I have been meaning to look into smart tabs as they seem to be a good thing all the way around.

I sure am going to enjoy this boat with the family as we have previously been in a 16ft 4ft wide princecraft canoe with the 3hp lightwin motor, But I am sure at some point I will miss the go anywhere capability of that big canoe.

 

[Frank Acampora]

Re: What to expect from my Motor/Hull combination.

Hmmm! 134 pounds? I guess that it is using some lighter castings than my 69 55.

 

[IamCanadian]

Re: What to expect from my Motor/Hull combination.

134 for the short and I think 142 for the long shaft.


And correction, The Motor has a 11.5 pitch prop*

 

[steelespike]

Re: What to expect from my Motor/Hull combination.

Don't be buying any props till you do some thorough testing.
I think your 66 may be hard to find props for.

 

[IamCanadian]

Re: What to expect from my Motor/Hull combination.

I don't plan on getting any props till I test things in the real world,

Michigan wheel makes props for them, 10.5, 11.5, 12.5 and 13.5 pitch.