300/440/550 650 pump

[insayne]

i know about blue printing but has anyone ever gone as far as to mod the hull to slap a sj pump in a 650sx? i mean i know the hull itself has some shortcomings but i kinda like the way it rides and i think with a bitchin pump it could be a much more solid ski.

 

[jetski9010]

I dont know if I have ever seen a SJ pump in one but I know you can fit the TBM cone in one if you put too much power to the pump. I might end up doing that with my 650sx motor swap build I am doing.

 

[insayne]

tbm cone... whats the benefit?

 

[kevbo]

i know about blue printing but has anyone ever gone as far as to mod the hull to slap a sj pump in a 650sx? i mean i know the hull itself has some shortcomings but i kinda like the way it rides and i think with a bitchin pump it could be a much more solid ski.

A SJ pump will fit but there is a little more to it than just slapping it in. You can get a lot more low speed thrust from the stock pump by using a re-pitched Solas KA-SC-I. This prop with a deep scoop grate works very well overall.

 

[WFO Speedracer]

Check out Fox's build thread , he installed a 650 pump in his.

 

[insayne]

I'll have to check out foxes build abd do more research on the tbm cone. I just figure the 140 or 144mm sj pump which ever it is would alliviate all of the cavitation issues these boats have but then again it could be the intake track leading to the pump also. I don't have any experience laying composites so I don't think reworking the intake track and then custom building an intake grate is something i can achieve

 

[insayne]

Hey kevbo what are people repitching them to? I have that prop. I've talked to an old x2 racer and he prefers a 14.5 with a kick for all the limited 650's he ran.

 

[kevbo]

The old props work fine once the ski is moving but struggle out of the hole. The old style hubs require more forced feeding than newer pointy ones. A stock Solas "I" is about right for a low port 750 or 800. A 750SXI or 650 will need some load removed. I start by lowering the leading edge by 1mm and raising the trailing edge by 2mm for a 650. Take some careful measurements and use a soft vise and hammer to bend the blades. Every boat/engine/rider combo is different and should be tuned individually for best performance. If you dont have a tach then tune by how fast it gets on the pipe and how hard it pulls. Make sure to use a stock 650 nozzle or an 84mm aftermarket.

 

[insayne]

Well the thing is it's a brand new solas I in there currently so I dunno if they changed anything or not. Also the boats not built exactly how I want it. I still need a dales bad attitude bump the timing strap a kiehin 42 carb to her and get a pjs or coffman exahust mani and a coffman rocket pipe

 

[jetski9010]

Here is the prop impros told me to run in my 650 pump that I have about 120 HP going to it. http://impros.com/store/index.php/i...skat-trak-kawasaki-140-75-swirl-impeller.html They are for the SXR but dave makes them fit the 650sx pump. Much larger hub then the older props out there and also has the swirl design. Should work out much better then a back in the day skat trak prop for the 650sx but we will see.

 

[insayne]

That definatly might be something to look into but I dunno where I am horsepower wise. Currently I'm running 205 pounds compression a modded stock pipe a drilled water box reed stuffer and a reed spacer op vortex air cleaner 38mm carb. Those are the motor mods so I dunno how much I'm making right now. My plan is to get a coffman or pjs exhaust manifold then get a coffman rocket pipe I'm working on closing a deal for a 42mm kiehin setup and I want to increase the timing and get a dales bad attitude cdi. I dunno how many ponies that build would make.

 

[kevbo]

That definatly might be something to look into but I dunno where I am horsepower wise. Currently I'm running 205 pounds compression a modded stock pipe a drilled water box reed stuffer and a reed spacer op vortex air cleaner 38mm carb. Those are the motor mods so I dunno how much I'm making right now. My plan is to get a coffman or pjs exhaust manifold then get a coffman rocket pipe I'm working on closing a deal for a 42mm kiehin setup and I want to increase the timing and get a dales bad attitude cdi. I dunno how many ponies that build would make.

Get rid of some compression and leave the timing stock if you plan to go full throttle for more than a few seconds.

 

[insayne]

I don't have any problem with my compression and or ridding wide open lol

 

[kevbo]

You wont be LOL when you add a pipe and "bump" the timing, unless $10/gal race fuel is used. Maybe things were different 20 years ago when everyone was sticking pistons while doing the same
mods that you are planning.

 

[insayne]

Oh I run a pump gas aviation fuel mix haha