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Can I put a biger engine in a challenger with a 787

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Ken

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Is there a conversion kit to put a biger engine in a challenger with a 787engine? or can i get put a super charger on it?
What can i do to get more hp?
thank you
Ken
 
man, wouldn't that be nice!

Welcome to the forum Ken......in short, no you cannot change the engine size without changing everything in the boat. A complete electrical change out to match the engine you'd be wanting to put in.
The modifications to make this happen would be more expensive than just buying a new boat with the 1503 4-TEC...
 
Yea, I changed out my 1997 challenger ...when I got done it was a new 200 speedster....oh yea I bought a new one...never mind!
 
change the engine

Is it the electrical that is cost so much?
or mounting the engine?
I was thinking about building a kit if I could get some feed back on what would be involved.
I wonder how well something like this would sale.
 
Hello!...

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Hello Ken, I have the same boat you have and quite frankly, very happy with the amount of horsepower she provides.
But if you want, you can do a few mods. You can't change the engine without changing the entire electrical system. Everything! The best way for you to add horsepower, would be through re-jetting your carbs.
R & D performance http://www.rd-performance.com/ is the best place for you to look for some tips in gaining some extra ponies.
Go check out the site and see what you can figure out.
One word of warning. When you start doing modifications, you start changing the life cycle of your engine. You'll find yourself constantly doing maintenance or repairs because pushing your engine harder, puts more stress on the crank, balance shaft, seals and a whole host of other parts that would normally last for years.
Good luck!....let us know what changes you make!

I just realized you did a double post, so I deleted the other one. Please keep this post as your active post for this information. Feel free to make as many post as you like, but not of the same subject. You'll get confusing answers. Thanks
 
Kit

Yes you are right. It will shorten the life of this engine to bust the power on it.
That is why I am interested in a larger engine kit.
The electrical the best i can see on the boat could stay the same like lights key so on. But the electrical that retains to the engine would need to be changed.
What I was thinking is taking the electrical off a bad boat with a good engine,
If I had a list of the electrical things that would need to be changed.

Than we get into the jet, what kind of deference would it make with just more hp.
Or will i need to look at replacing it to?
Thank you for your reply
 
Axial flow pump....

No, you shouldn't have to change the single stage, axial flow pump since seadoo has used this model in serveral different applications.
As for changing out the motor, you'd also have to look at weight, motor mount and measured distance for the drive shaft. I'm not saying it can't be done and I don't have any hard core research to support that fact, only in conversation with others.
Like you said, lights and the bilge pump, etc....these are generic, but when you get into other components, the mpem has to identify these to allow the boats electrical circuit to be complete. I know when I was reading the manual for the 2005 4-TEC (which I'm sure your not wanting to use) engine, you have to have the mpem re-programmed to add any other accessory, like a bilge pump. Don't ask me why, I don't know that. It's just what I've read. In what your wanting to do, if you put in, lets say a 947, then where you may have 2 wires coming from your neutral safety switch, the other may have 3 wires.
If I were going to create more ponies for my boat, I'd probably trick out the 787. Although what I said about the engines life span is true, the 787 is one of the most reliable and simple motors to work with. I tear mine apart on a regular basis just to look for any potential problem or to keep it clean and the parts free. When I first got it, all the nuts and bolts were practically impossible to remove. I had to cut the carb studs on the pto side just to be able to rebuild it. Now, all my bolts and studs are torqued properly and removed yearly for inspection............sorry, going off on another tangent. To do what your wanting to do, you'll need to have some type of blue print for motor weight, hull design etc.....
There was a video thread in the forum last year where someone supposedly put a mazda engine in a boat. But all you ever saw was the engine. For me, there was no proof that the boat was actually powered by that motor. And another video here just recently of a pwc powered by a diesel engine.
You've got a good challenge on your hands. I'd be interested to see what you end up doing. Keep us up to date!........
 
Ken no matter what you do to make it go faster you will have your hands full. Weather you modify the 787 or change out the full engine drive it will be a project. Why not just buy a bigger faster seadoo jet boat. This will save you a lot of aggravation and you will be on the water quicker. It more than likely will be cheaper too!

Karl
 
Change the engine

Seadoosnipe that was the feed back I needed. Thank you. What was the biggest engine that came with this frame. Did the 947 come with this frame?
I would like to see every angle of this project before I start. I may be able to document everything with cad drawings and make a kit that would make it a easer project. I do have access to a very well equipped machine shop and have done a lot of proto-typing, just not with boats. The first one may be hard. But if there is a market the project may be worth it. So if any one has a drawing of the boat and different engine that may work with this frame please let me know.
Thank you
 
Ken it appears that you have the knowledge to complete this project at hand. I see a lot of members come in here with a dream of doing such a project with no Skills or idea what they are up against. Cad drawings will be a great help in designing this project. Sorry I sounded pessimistic in my post, but you got to admit there isn't a quick fix to do a change over. Good luck, and if you have any other technical questions I'm sure you'll get an answer. This forum has a mixed batch of members, from all walks of life.

Karl
 
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