300/440/550 Conversion Ski's

[professor961]

So here's a thread we can dedicate to conversion ski's - pics, discussion, tech, how to, you name it.

This can be a good thread for people during their build. Impeller choices, electrical, exhaust problems, etc.

Those who have not ridden a conversion ski don't know what they are missing!

Let get this thread started!

Prof

 

[rab2009]

hey professor it looks like you have a bit of fiberglass work to do on that hull.

jk it looks cool

 

[Conquistador]

http://www.x-h2o.com/threads/20940

 

[3wheelerdude]

http://www.x-h2o.com/threads/20940

Wow Seems like you covered alot of ground on that jump.......talk about distance. Nice job.

 

[747checker]

Takin my 440 and swapping with a 550 and doin a bit more to it.
ski purchased may 07...came with
-coffman waterbox
-west coast ride plate
-aftermarket exhaust manifold
-west coast arrestor
other than that she was completely stock and looked terrible. guy i purchased it from spray bombed it blaze orange and black and then let it sit in the sun. everything was faded and chalky.

Project name...RUBBER HOSE RACER (due to keeping the original rubber exterior exhaust hose.)
Stage 1. paint. sanded down the hull, threw on some white and metallic blue. then had the idea to do pink accent strips. didnt put enough clear on and the paint was not very durable while riding. again new paint to come with the motor swap this x-mas
Stage 2. motor/more goodies
-pp 550 topend. going to get ported and polished
-Rogo high compression head...runs about 210 psi
-westcoast exhaust
-pjs 16 pitch prop
-44mm sbn carb with ocean pro arrestor
-foot holds(unsure of what im doing for those though)
-450 gpm bilge
got a few pics of original paint and my first shot at painting it...

 

[Conquistador]

Wow Seems like you covered alot of ground on that jump.......talk about distance. Nice job.

thanks man:usa2: I am stoked after this past weekend. probably the best I've ridden since that was taken over 15 months ago!

 

[superjetnj]

For you conversion guys, I have a 440 with a 650 in it, coffman pipe, front exhaust delete, rear only 1-1/2, 550 sx pump, forgot the impeller pitch, but it is on the low side, the only way to get it to go is to hop it out of the water a couple of times, and then it is a rocket ship. I've tried different water boxes, right now running a supertrap w/o any baffles, sounds like a hotsaw. Ski has awesome topend, when you can get it there, but the bottom is terrible. Any suggestions?

 

[Conquistador]

For you conversion guys, I have a 440 with a 650 in it, coffman pipe, front exhaust delete, rear only 1-1/2, 550 sx pump, forgot the impeller pitch, but it is on the low side, the only way to get it to go is to hop it out of the water a couple of times, and then it is a rocket ship. I've tried different water boxes, right now running a supertrap w/o any baffles, sounds like a hotsaw. Ski has awesome topend, when you can get it there, but the bottom is terrible. Any suggestions?

a 440 pump might night hurt. maybe a 15 degree pitch impeller?

 

[Flat Brapp]

for them conversion skis you need a steep pitch like 17 degree.

 

[professor961]

For you conversion guys, I have a 440 with a 650 in it, coffman pipe, front exhaust delete, rear only 1-1/2, 550 sx pump, forgot the impeller pitch, but it is on the low side, the only way to get it to go is to hop it out of the water a couple of times, and then it is a rocket ship. I've tried different water boxes, right now running a supertrap w/o any baffles, sounds like a hotsaw. Ski has awesome topend, when you can get it there, but the bottom is terrible. Any suggestions?

The 550SX pump is the ticket for the conversion ski. I have a 550 pump and was very pleased with it's performance. As for your impeller pitch, you are stating you have great top end and terrible bottom end. If you didn't build the ski and don't know what pitch is there, I'd suggest it's a proper tall impeller like mine - I have a 19 straight - and your engine is weak.
The 650 when it's making proper power will have great low end even with the 19. The top end is more than basically anyone can hang on to.
If you have a low pitch impeller, you should have too much bottom end and really flat on top. Try to identify the actual pitch and determine the health of your engine.

Pics of my modified exhaust manifold coming soon. It's back from the machine shop and ready to install.

Prof

Oh, and Rab - Randy Rhodes was one of the best guitarists ever. Ever. Ever.

 

[WFO Speedracer]

My THUNDERJET conversion project.

http://www.x-h2o.com/threads/22925

 

[professor961]

The ski has been sitting around far too long and the riding weather is approaching the end of the season. I finally have the exhaust manifold ready to go in. I used an OEM manifold, had the exhaust bracket cut back, and the hole relocated down .750". This makes more room for the pipe.

For all you guys doing a conversion ski, I suggest cutting back the exhaust manifold bracket. Mine was cut down .350" and hole lowered .750". Seems to me the right numbers to have room all the way around the pipe.

Prof

 

[Motorheads5]

http://www.pwctoday.com/showthread.php?t=150901&highlight=650+conversion

The 550 / 650 conversion ski is by far the best bang for the buck ski to build and have soooooo much fun on they ripp.