SJ power over boat wake

You could have a number of things. Tired engine, improper carb tune, burned up, or chipped impeller causing cavitation. Has the engine been gone through that you know of? A compression check and a engine leakdown test to make sure you dont have an air leak anywhere. You could have water leaking into the combustion chamber or exhaust somewhere. I've ridden properly setup stock superjets than ran really well. If the engine is mechanically sound and the carbs are clean and in good mechanical order, then look at the impeller and pump. I'd definitely make sure the engine is in good condition before adding a pipe or a higher compression head. If the engine isnt sound, adding any bolt ons like that will kill the engine in a short time.
 
Location
dfw
You will seldom ever have "enough" power. It will cost $2-3000 To make a 701-760 good, and an additional $3000 for a "better" aftermarket large bore cylinder. From there it gets even more $$$ for the "best" stroker setup. Then you need a short hull in order to get it all out of the water.
 
I learned to ride surfing a boat wake at like 17 mph on a stock 650 superjet. Stay on the throttle.

Bored nozzle, 13/16 cutback, 9/15 hooker, or jetworks A prop. Don't even need a pipe to have fun
 
I probably should go through the engine at some point. I bought it used and not sure of the history. It's unmolested and in pristine condition, visually. It's been in my hands for 5 years now and haven't had a real reason to touch the engine. The compression showed 150 PSI when I bought it and still shows 150 PSI. I replaced the impeller and wear ring last year. I added a hooker 9/15 which made a very small improvement.. What is a cutback?

I am mostly a weekend rec. rider so I am not trying to send it to the moon. However, it would be nice if it had a little more punch when at the bottom of wake. Takes off from a start pretty well. This is the only superjet I have ridden, so unfortunately for me, I have nothing to compare it with. Maybe that's just how it is. How about these waterlogged trays that I hear about?
You could have a number of things. Tired engine, improper carb tune, burned up, or chipped impeller causing cavitation. Has the engine been gone through that you know of? A compression check and a engine leakdown test to make sure you dont have an air leak anywhere. You could have water leaking into the combustion chamber or exhaust somewhere. I've ridden properly setup stock superjets than ran really well. If the engine is mechanically sound and the carbs are clean and in good mechanical order, then look at the impeller and pump. I'd definitely make sure the engine is in good condition before adding a pipe or a higher compression head. If the engine isnt sound, adding any bolt ons like that will kill the engine in a short time.
 

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What is a cutback?

The back of the impeller hub is cut back typically 5-7mm. It allows the back edge of the impeller blades to get as close as possible to the pump stator veins. It's suppose to make less pump slippage and better hook up. I have always had my local machine shop do it for me.
 
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The back of the impeller hub is cut back typically 5-7mm. It allows the back edge of the impeller blades to get as close as possible to the pump stator veins. It's suppose to make less pump slippage and better hook up. I have always had my local machine shop do it for me.
Interesting. Is there a notable difference?
 

bored&stroked

Urban redneck
Location
AZ
I doubt it will make much of a difference on a prop that is already known for excellent hookup and bottem end power....
A 701 superjet with a hooker 9/15 is not lacking response power wise. You need to time the throttle better, and get a pipe if you want more power.
 
Location
Ohio
I doubt it will make much of a difference on a prop that is already known for excellent hookup and bottem end power....
A 701 superjet with a hooker 9/15 is not lacking response power wise. You need to time the throttle better, and get a pipe if you want more power.
He has a stock 99 SJ. Oops I see he added a 9/15. I HHHAAAATTTEEEE that prop! I gave one away years ago.
 
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Location
Ohio
OP I'll hook you up the exact way I was hooked up by the best in this sport/hobby.

I was told and did exactly what I was told and have been smiling ever since....over a dozen years.

Call Impros in California and ask for a 13/17 repitched to a 13/16 and cutback 3mm. They have great notes (even though Dave is gone) and will know exactly what you are asking for.

Then reach out to anyone on here that can bore your nozzle to max and enjoy!!
 
Location
Ohio
Actually nevermind IMO you are stuck with that expensive prop now so just keep spending money to make that prop work I guess. More compression, Bpipe?
 

bored&stroked

Urban redneck
Location
AZ
Well now I really want to try a cutback 13/16 lol
The big hub skat I'm currently running does not impress me. It doesn't feel any different then the old solas original line prop I had in there before.
 
Location
Ohio
Well now I really want to try a cutback 13/16 lol
The big hub skat I'm currently running does not impress me. It doesn't feel any different then the old solas original line prop I had in there before.
13/16...bored nozzle...stock come. Apparently old school. I have tried quite a few prop, nozzle, cone combos over the years and this one is it IMO. I would love for someone to tell me why! Lol.
 
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