951 Swap X2

WFO Speedracer

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I looked at that and the issues revolved around the exhaust pipe and waterbox, there is room for either to fit without major modifications.
 

WFO Speedracer

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I am just interested to see where everything is going to go , I test fit one in mine years ago , to say it's going to be a tight squeeze is an understatement , the 787 barely squeezes in there and that's with a hollow tubbie on the Left side and a carbon fiber-kevlar hood with no hood liner.
 
A couple of things to think about:

The 951 is a heavy fuel user. Might get two 12-lap motos out of a 5 gallon Tank, maybe.

The 951 is heavy, Will make the X2 Hull sink even deeper which will result in a lot of Drag that will negate the extra Horsepower benefits. Front Sponsons and overall widening of the Hull Bottom to gain Buoyancy will definitely help in reducing the Drag.

The X2 Hood will need to be modified to allow enough Air Flow to feed the 951 Beast. But in a way that minimizes the flooding of the Engine Bay, which will be a serious issue.

The X2 Pump will need to be upsized to benefit from all the extra Horsepower.

Enjoy the Conversion Build.
 

Jr.

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Man, thats a lot of work for sure! Back in the beginning of Ski GP. Several guys tried going the 951 route.
sounded good going in. Boats were fast initially, but many struggled to finish a moto. I was not directly involved with those boats, i was doing tech. So can not say what the issues were? Just know, none I ever saw made it into the top 5. I do see 951 in HX / Sport GP and those seem to stay together. X2 is a very Wet hull inside as you know. No motor like injesting water! Good luck!

P
 
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X2s are the most difficult to find room for much of anything. I think the small Yamaha triple would fit and work well but making it happen is beyond the ability of most people.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
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Man, thats a lot of work for sure! Back in the beginning of Ski GP. Several guys tried going the 951 route.
sounded good going in. Boats were fast initially, but many struggled to finish a moto. I was not directly involved with those boats, i was doing tech. So can not say what the issues were? Just know, none I ever saw made it into the top 5. I do see 951 in HX / Sport GP and those seem to stay together. X2 is a very Wet hull inside as you know. No motor like injesting water! Good luck!

P
951's in particular do not fare well with water ingestion, usually if you get water in it one time it's time for a top end rebuild.
The first 951's were set up with airboxes with snorkels on both ends, those sucked in water like a hoover vacuum and instantly killed the top ends , so they redesigned the airboxes with the ones that took in air around the exhaust pipe flange area and we had to rejet the carbs for the new airbox setups.

The problem with that was the exhaust gaskets leaked at the flange and at high RPM's it pushed water right into the new air intake snorkels again killing the top end , as a last resort they made a rubber piece we referred to as the diaper that went around the entire manifold to pipe joint. this didn't cure the leak but allowed it to slowly trickle down the exhaust manifold.

Later they redesigned the exhaust manifolds to accept an o-ring but the areas around the o-rings are quite thin and with age and saltwater use they give way and create a huge water leak.

So your main issue is going to be keeping water out of the engine , I am really not sure how you are going to do that in a X2 hull with the carbs mounted as low as they are.
 
I'm wondering why a 951 would be more sensitive to water ingestion than say a dasa 970 (similar bore and stroke), and I'm also surprised that designing an airbox is so hard. But, I've never tried, so maybe it really is that hard.

Open pod filters mounted in that position do seem pretty sketch in an x2.

This is one of those deals where once in a while somebody comes along and does something out of the ordinary that is really awesome, but usually they just go nowhere.

I hope this ends up awesome.

I love x2's and have daydreamed about all kinds of oddball motor swaps but I'm convinced a really good kawi twin can be more than enough.
 

WFO Speedracer

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I have no experience whatsoever with DASA 970's but plenty with Seadoo 951's so I can't say in that respect, as far as the out of the box thing I totally get that aspect of it and I too hope he is successful.
I went with the 787, almost as much HP, way lighter , but here is the engine I really want to see someone put in an X2.

95 hp bone stock 6600 rpm , with big bore 800 mods and porting 162 HP.


 
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Location
dfw
All the twins will need a decent pipe which takes up a lot of room. A laydown pipe may fit at the expense of fuel capacity and a muffler. Picture a 63m or 65u with the extra cylinder pushed to the rear against a shortened driveshaft. Then make an adapter from the front outlet of the exhaust manifold to a 4" hose running to a custom free flowing waterbox. The tower may need to be cut for the rear carb and exhaust manifold. A Kawasaki 1100 may be a little easier to adapt by using only the forward facing parts of the stock exhaust. There should be enough room for everything with the stock tank. You would have 110-130hp on pump gas. The pump may be iffy though..
 
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" Wont work just wont work " ............. Everything works, there is a solution to all ...... and its a great project !! Keep it up

I am sure the engine placement / rotation is the key as with all conversion projects
 
I have no experience whatsoever with DASA 970's but plenty with Seadoo 951's so I can't say in that respect, as far as the out of the box thing I totally get that aspect of it and I too hope he is successful.
I went with the 787, almost as much HP, way lighter , but here is the engine I really want to see someone put in an X2.

95 hp bone stock 6600 rpm , with big bore 800 mods and porting 162 HP.


That a snowmobile engine? Curious on the power output. It looks like it has a lot of transfer area based on how the front of the cylinder by the flywheel end is bulged out for more transfer volume. similar to how the tpe cylinders are built.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
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That a snowmobile engine? Curious on the power output. It looks like it has a lot of transfer area based on how the front of the cylinder by the flywheel end is bulged out for more transfer volume. similar to how the tpe cylinders are built.
Yes Polaris smowmow but unlike a like of snowmows it's fairly low RPM around 7000 , 95 HP stock , up to 162 HP with mods.
There are some Skidoo snowmow engines that turn close to 11.000 RPMs.
 
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Getting the 148 zxi pump mocked up and ground down to fit inside this little tunnel. Appreciate all the input! We are pretty dedicated to making this work, stay tuned!IMG_3439.jpeg
 

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Pipe showed up today, it’s definitely gonna work. Minor modifications to the hood will be done with carbon. Had to take some material off the pipe. I think we are going to weld an outlet off the chamber firing forward into a custom waterbox. That’s up next!
 

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Carbon fiber water box, boxed in underneath seat for battery & rear exhaust routing
 

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