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Performance Impeller?

ADoyle3

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Scarab
Year
2019
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165 ID
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Hey... I am looking into getting the "Scarab 250 Impeller Single Engine 2016-Up" from Impellers.com when they offer them in June... Has anyone tried an impeller upgrade in one of these 250HP boats? Should you use steel wear rings? There don't seem to be many performance upgrade options at this point. They also offer a machining service (reshape, polish) Again if anyone has tried this I am interested in the feed back?? Scarab Impellers at wholesale priced impeller
 

wango tango

Jet Boat Addict
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2017
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HO Impulse
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Don't go stainless not needed, they offer a 15/19 impeller which I have in my 195, nice improvement. 159mm impeller and wearing is all they offer in that pitch, replace them both(wearing and impeller)
 

ADoyle3

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The 2019 is the 161mm ring and Impeller. They claim they won't have them until JUNE...
 

wango tango

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The 2019 is the 161mm ring and Impeller. They claim they won't have them until JUNE...
Even though you have 161mm you can go with 159 if you change both impeller and wearing.
 

BarbaraAnn

Active Member
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Scarab
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2014
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195 ID
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Speaking directly to one of the representatives from Scarab they recommend the impeller upgrade Stainless or Otherwise to achieve either faster takeoff or higher top end. You trade low end for high, unless you can improve the torque-power curve. Remove everything except the drivers seat, throwable, and fire extinguisher and zero passengers. Then let her rip. I've been told by an engineer that putting in the Pulstar Spark plugs with 97 Shell Octane Gasoline will improve horsepower noticeably. You are supposed to Gap them about 2-4 10,000inch smaller gap than standard gap (i.e. 0.025).
 

Winerocks

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If you are searching for Scarab-specific performance upgrades, there are very few. The BRP powerplant and jet pump are common to SeaDoo pwc's, and there are plenty of ridiculous upgrades on that front. The GreenHulk forum is a great resource....but keep in mind that with many of these upgrades you will likely see a decrease in engine longevity.
My 2 cents on the wear ring: There is and always should be a weak link in the drive. From the factory, this is the plastic wear ring. If this is replaced with something stronger, then the weak link becomes something else; either the impeller or the driveshaft. If you suck up something other than weeds or sticks, the chances of a catastrophic failure are increased.
 

Gozills

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Scarab
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2020
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165 ID
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Speaking directly to one of the representatives from Scarab they recommend the impeller upgrade Stainless or Otherwise to achieve either faster takeoff or higher top end. You trade low end for high, unless you can improve the torque-power curve. Remove everything except the drivers seat, throwable, and fire extinguisher and zero passengers. Then let her rip. I've been told by an engineer that putting in the Pulstar Spark plugs with 97 Shell Octane Gasoline will improve horsepower noticeably. You are supposed to Gap them about 2-4 10,000inch smaller gap than standard gap (i.e. 0.025).
someone is blowing smoke up your skirt! Lol
 

Gozills

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Scarab
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2020
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165 ID
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Oo
Don't go stainless not needed, they offer a 15/19 impeller which I have in my 195, nice improvement. 159mm impeller and wearing is all they offer in that pitch, replace them both(wearing and impeller)
I don’t even know of a scarab or seadoo impeller thats not stainless
 

BarbaraAnn

Active Member
Messages
18
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Boat Make
Scarab
Year
2014
Boat Model
195 ID
Boat Length
19
If you are searching for Scarab-specific performance upgrades, there are very few. The BRP powerplant and jet pump are common to SeaDoo pwc's, and there are plenty of ridiculous upgrades on that front. The GreenHulk forum is a great resource....but keep in mind that with many of these upgrades you will likely see a decrease in engine longevity.
My 2 cents on the wear ring: There is and always should be a weak link in the drive. From the factory, this is the plastic wear ring. If this is replaced with something stronger, then the weak link becomes something else; either the impeller or the driveshaft. If you suck up something other than weeds or sticks, the chances of a catastrophic failure are increased.
Thanks. I followed up with one of the guys at Scarab, who confirmed what you already knew! He recommended sticking to rubberized wear rings for the same reasons you stated. Thanks for your sensible advice.
 

Winerocks

Jet Boat Addict
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Location
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Scarab
Year
2015
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HO Impulse
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21
Thanks. I followed up with one of the guys at Scarab, who confirmed what you already knew! He recommended sticking to rubberized wear rings for the same reasons you stated. Thanks for your sensible advice.
No sweat! Some people don’t mind sacrificing
longevity and reliability for speed....not me.
 

BarbaraAnn

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195 ID
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someone is blowing smoke up your skirt! Lol
Besid we s that, I mistyped the gap. Should have typed .25-.28in. On the Plugs I've used the Pulstar in my MSP and have noticed higher efficiency. HP increase would be about 3-4hp est.
 

Ronnie

Jetboaters Fleet Admiral
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You don’t have to buy a new impeller to improve its performance characteristics, just have it repitched by someplace like impros. The thing to remember is that stock implellers are supposedly already pitched for optimum acceleration and top speed. If you repitch an impeller for better acceleration your top speed will decrease and vise versa. As for wear rings if the gap between one and the impeller becomes to large you can coat the impeller facing side with an epoxy like JB weld to close the gap. Spark plugs, I’ve been installing iridium plugs for years which are two to four times the cost of standard plugs. If they perform any better than standard plugs In terms of acceleration, top speed or mpg I haven’t noticed but still use them out of habit and only replace them as often as I would standard plugs.
 
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