I have made up my mind to build my own boat and with it my own mud motors. I know how to work on Johnsons and Evinrudes, but just want simpler motors. I am going to build my own boat because it's the only way to get the features I want and still be able to do most of what I want with it. The boat is this: http://www.spirainternational.com/hp_galv.php

Kinda of a big boat, 19' long give or take and 69" wide at the waterline.
And I'm thinking that I either need a Vanguard 37hp or 2, 22hp Predators to be able to get around with any speed given the hull weight of 1000 lbs. Most of the time the max load would be 5 adults, 1 munchkin, and 1 dog plus fishing gear and an ice chest. I don't duck hunt, but wouldn't mind trying to deer hunt along the river. Most of the fishing would be on the river and snaking up some of the smaller creeks here in NorCal. Some lake fishing. Main reason I chose this boat plan is that I can build into it a bow ramp is so that it would be easier for little ones to get onboard and anyone that can't walk as good. I've got a buddy who is in a wheelchair too, it'd be kinda cool to get him on the water. I like the idea of going with smaller engines since there seems to be a whole lot more peformance stuff for them but given the size of the boat and my payload, I'm not sure I could get enough hp out of a 16. I did find small engine turbos for engines up to 600cc for 350$ and my eyes kinda glazed over for a bit and I may have started to drool.

So my main question is will two 22hp Predators do the job with some basic mods to the engine? I haven't decided on a long tail or a surface drive yet.

This is my first homemade boat and first homemade motor so forgive me if these questions are a bit basic.

Joel
norcal

Man that is def different. With the load your talking I'd be thinking outboard .

Longtails or surface drives?

Do you have a NEED for a mud motor? By the time you mod an engine for performance, it's not going to be as reliable or strong as a correctly sized outboard.

Keep in mind, with your plan everything will be custom. I've worked on the Predators, but there isn't an after market for them. A long tail will be easier to build yourself and much more reliable. Especially if you do the build yourself. With the load, dual engines would be better...however you don't see many dual long tail rigs. I have no experience and I'm not saying it can't be done. Dual surface drives are becoming more popular.

I'd start by looking at boat reviews here - specifically reviews from guys that carry a heavy load. See what motor and mods they are using, and how it performs with the load.

Not trying to discourage you from doing it yourself...I'm a big DIY fan. There are likely lots of builders on here willing to build a hull to meet your needs for accessibility at the bow. You might consider talking to one of them for an opinion. I'll recommend Uncle J Custom Boats as one place to start. Even if you dont have him build a boat, I'd bet he can give you some good advice.

Just keep in mind...you're looking at moving a lot of weight for a mud motor, but it can be done.

Whichever drive I could get the most power out of.

I have thought about an inboard as well. An air cooled diesel would make fueling it easier. There's a 70hp Hatz diesel for sale up the road for 1000$, but I wonder if it would be worth the weight penalty.

I haven't decided one way or the other, I'm still just spit balling here.

Thanks

Joel
norcal

Check out Arnsen surface drives on the internet. You can put about any size motor on them clear upto gas turbines. And motor will be inboard.

I would suggest a talk with stualaska. Out of everyone here, he's likely been the most out of the box with boat weights and absurd loads. You'll get plenty of this and that won't work, but if you have the thrust to get enough speed to create the lift, it'll work fine.