783 stroker in a 550sx

[huddleston]

44 mikuni carbs,west coast 650 pipe and a billit crank on 0 deg,any thoughts on props?

 

[Polish jet pilot]

Before we go to props please tell us the history and specs of this baby - I love it. Did you run it before? What crank does it use, what cylinders, what is the piston size? ANd please more engine pics

 

[Waternut]

Looks like a 750. If you say it's stroked, I'm guessing 2mm (76mm stroke) stroker with an 81mm (+1mm) bore. Also looks like a a girdled head without the girdle kit and stock ignition??? okey:

First thing is first, you can't run a 550 pump with a motor like that. It just won't work and even if it does, it's a waste. Get a 140mm kawi or 144mm SJ pump and do some customizing. People have run 550 pumps in a 750/550 conversion and they say it doesn't work well at all.

 

[upstand2]

Thats a cool boat! I say get a mag pump.

 

[Polish jet pilot]

So what is the base engine in this boat? A 550 or a 750?? Sorry to ask again, but I did not get any confitrmation.... regarding the pump, there are some guys running 750's with a 550 pump and some say it is OK!

 

[huddleston]

it's a 750 +3 stroker and a rad crank, i'm not sure on the bore but i think he said 83mm bore but don't hold me to it, i've rode it twice but still tuning and i need a set of reed stuffers.and it was freakin cold out we had ice on our pants and ski's i just couldn't wait till spring.it has a 650 group k flywheel and the 550 ig. i was gonna go with jetinetics total loss but the exsposed parts are rediculus. if you guys think i need a pump,do you know were to get and make fit. but when i rode it not tuned it was just a little faster than my buddy's 750

 

[madscientist]

check for foximus's build he sectioned a 650 tunnel into his and is runnin a 701

 

[huddleston]

it's a 750 +3 stroker and a rad crank, i'm not sure on the bore but i think he said 83mm bore but don't hold me to it, i've rode it twice but still tuning and i need a set of reed stuffers.and it was freakin cold out we had ice on our pants and ski's i just couldn't wait till spring.it has a 650 group k flywheel and the 550 ig. i was gonna go with jetinetics total loss but the exsposed parts are rediculus. if you guys think i need a pump,do you know were to get and make fit. but when i rode it not tuned it was just a little faster than my buddy's 750

pic

 

[Idok]

it's a 750 +3 stroker and a rad crank, i'm not sure on the bore but i think he said 83mm bore but don't hold me to it, i've rode it twice but still tuning and i need a set of reed stuffers.and it was freakin cold out we had ice on our pants and ski's i just couldn't wait till spring.it has a 650 group k flywheel and the 550 ig. i was gonna go with jetinetics total loss but the exsposed parts are rediculus. if you guys think i need a pump,do you know were to get and make fit. but when i rode it not tuned it was just a little faster than my buddy's 750

be careful riding in water temps like that...especially with a poorly tuned motor you are heading for a cold seizure

 

[Waternut]

Well if it's a 3mm stroker crank it has to be an 80.5mm bore to equal 783.

Just for sh*ts and giggles... If it's a real stroker crank, I would think you could easily get over $1k for that engine. Just something to think about.

 

[huddleston]

Well if it's a 3mm stroker crank it has to be an 80.5mm bore to equal 783.

Just for sh*ts and giggles... If it's a real stroker crank, I would think you could easily get over $1k for that engine. Just something to think about.

yeah i've got 2k in it with carbs and pipe,any suggestions on timing,and tuning it

 

[dbrutherford]

Where are you located?

 

[huddleston]

beckley

 

[dbrutherford]

I thought WV since your location title. I will be down in Beckly next Monday and Tuesday for work. If you want to meet up and ride this summer at Summersville, Sutton, Cheat, Tygart, ect... just shoot me a PM.

 

[huddleston]

hellsyeah can you help me tune this beast, i'm down to ride anywhere anytime,what do you ride,any good secret spots? i've seen a couple but my girl doesn't like shallows

 

[dbrutherford]

I live in Fairmont. I typically just ride the Mongehela and Tygart Rivers. I don't like the no wake zones at the lakes. I lived out of state the past two summers so I didn't ride any here in WV. But I am back now in WV and wanting to try out all the other lakes I haven't ridden. Typically you find one that is water cop friendly and has some cruiser traffic, you stick to it!

 

[cjbchopper]

I have done this same 550/750 conversion. The ski was a bit faster on top, but the bottom end power was the same with the 550 reed motor. The 750 motor just needs the larger pump. I had a mint 550 pump with a brand new stainless prop and I could not get the thing to hook up. You should just put that motor into a 750 hull, you would get much more out of the hole with the larger pump and inlet on the 750 hull.

 

[huddleston]

thats the plan i will upgrade to a better hull i just figured to start win the motor and then the hull, maybe an eme hull would be nice:stups:

 

[Foximus]

If youve done a 750/550 conversion before you know that a extremely aggresive blue printed pump and tuned impeller is KEY. And yes, a properly setup pump will hook decently.


You should also just go ahead and take your motor out and put many many layers of reinforcement in that ski. I broke my hull twice already.

 

[BBYamaha]

I saw a chode in pheonix that said he had a 1000cc motor in a 550, he said all you had to do was put in a 900cc motor and then have it dynoed and wala instant 1000cc. He then said to stop my nonsense (I asked how he did it and if he had picks) What a fag, I know it was bs or a great build, he never responded to my questions after the 1st email and he sold the ski for 2K.