Superjet GP1200 engine conversion

[jet-shed]

Hi all,

This winter, we built a second SJ with GP1200 engine in it.

With the first one, we routed the exhaust back through the left side of the hull. This time, we decided to take the original route through the nose to improve weight distribution and buoyancy.

We milled two 20mm aluminum front engine mounts, fit the 155mm GP1200 pump, relocated the battery and exhaust in the nose on a new bracket and it all fits nicely in place.

Here are some pictures of the project.











Tonight, we will make the first test run. We'll let you know how it runs.

Good luck!

 

[ItsRixter]

so we never heard back ???? did the motor just rip out of the hull and sink???

 

[jetpilot08]

x2

I'm curious to see this this thing run! :brap:

 

[Waternut]

Looks awesome! What kind of ride time do you get out of that fuel tank though? 5-10 minutes?

 

[jet-shed]

Hi all,

The ski worked well and didn't sink although we lost the hood due to the stress on the ski and a bad hood fit.

My camera took 346MB for a 2 minute film so it takes some effort to upload. But I'll post a link for sure.

Compared to the MK1 SJ1200 we have some work to do on the pump. The MK1 has a 144mm magnum pump with 17/24 impeller and the MK2 uses the stock GP1200 155mm pump (don't know the impeller pitch). Lots of bottom end but too little top speed (MK1 is faster). Tomorrow we'll be testing a 45mm pump cone extension to increase nozzle exit speed. Any advice is welcome!

The tank (still 8 liters - about 2 gallons) holds for 15 minutes full; that's enough. This one is a $30 kart tank - we're planning a custom fit aluminum tank to gain maybe a gallon but it's no priority.

We seriously cut up the hood to make enough space for the exhaust - really don't want to lose it again with no foam left in the nose and 20 kgs more engine. We initially heated up the inner liner and just pressed the hood over the engine with a wet towel in between to cool it off but that's not enough.

The exhaust setup works well - the ski is more balanced then MK1 SJ1200 and the added weight in the nose works OK.

Some 40 mins of uploading left - will post the video link asap.

Good luck,

 

[jet-shed]

Here's the link:

enjoy!

 

[Waternut]

Hard for me to tell any difference from a stock motor in the video. The 1200's have really good acceleration in a couch that weighs more than twice as much as the SJ. That thing should be yanking your arms off and hitting top speed in no time. Looks and sounds like you've got some tuning left to do. Good luck though, I'd like to see it work.

 

[dbrutherford]

I have some pictures of several different tripple engine SJ's. Big engine swaps always intrest me.

DBR

 

[Kennay]

1. Easily visible that it is much faster than a stock ski
2. Sounds 1200 awesome
3. Not as fast as I was expecting (Yet)
4. Nice job!

 

[blaster800]

Great engine swap ! Nice work

 

[PancakePete]

that looks like fun.

 

[ItsRixter]

Hard for me to tell any difference from a stock motor in the video. The 1200's have really good acceleration in a couch that weighs more than twice as much as the SJ. That thing should be yanking your arms off and hitting top speed in no time. Looks and sounds like you've got some tuning left to do. Good luck though, I'd like to see it work.

x2

I thought I'd see the ski pop out of the water at least once....or the rider's arms rip out of the shoulder sockets

 

[Vumad]

Bump. I want more info.

Did this motor bolt right into the rear motor mounts and line up with the driveshaft with just the addition of the front motor mounts?

Any other info. I have a motor I can drop into my Kawi's, or w/e.

 

[AtomicPunk]

Bump. I want more info.

Did this motor bolt right into the rear motor mounts and line up with the driveshaft with just the addition of the front motor mounts?

Any other info. I have a motor I can drop into my Kawi's, or w/e.

you must like wrenching more than riding.....

 

[Vumad]

you must like wrenching more than riding.....

Haven't been doing any wrenching. Been doing major construction at the house. X2 is in good shape. My quads run perfect. About to finish up the house. Will have time to ride and I need to build something for my girlfriend. I have a GP1200 for her now but no title. I have several extra X2 hulls. My current X2 is going to stay just the way it is, running strong.

 

[tom21]

I have a free xl700 hull you can put that 1200 into. clear title. ski is gonna need work. I just want the motor/ebox

 

[jerrybboy]

Grasbroek.. This thing is a monster..

Real nice build. The black one was your first rebuild ?
I've got the kawasaki whick flooded last year.
I bought the trailer of a friend of yours from "De essen"

Greetings