does anyone know how to select an impeller

[SurferSmurf]

i am runnin a ported 771 motor with a b-pipe plus all the other standard supporting mods. i have a mag pump with a 14/19 impeller. my ski pulls very hard but i was wondering if i could do better with a different pitch. if any one has any real experienced input it would be appreciated.

 

[kevbo]

First you need to find the full throttle RPM between 20-35 mph.

 

[vitalikol]

Call Dave at Impros, it's only sudgestion I can make

 

[djkorn1]

You are looking for more low end?

 

[SUPERTUNE]

Do you have 96-up aluminum nozzle?
Is the nozzle taper bored? What size?
Intake grates can make a difference between brands.
Is this a 144mm pump?
Is this a set back impeller?
Depends also how the engine is setup...
Compression, porting, ignition and timing curve all can effect how the pump is setup.

 

[SurferSmurf]

its a 144mm 12 vein mag pump with a pro-tec trim setup that was flipped (nozzle size is whatever protec make them, ive never measured it). its a worx intake grate. the impeller is not set back. im not 100% sure of the motor setup or the timing and all that. it is ported but im not sure who did it and the compresion is 165ps1. as far as timing goes its a pro tec CDI with the stator in the stock position.

the ski runs good but impeller pitch came up in conversation on the beach and i was wonderin if a different one would actually perform better.

 

[MADMAT]

His ski rips hard with his 14/19. He wants to know if a 12/17-3mm to -7mm would give a little more bottom.

 

[AtomicPunk]

His ski rips hard with his 14/19. He wants to know if a 12/17-3mm to -7mm would give a little more bottom.

if it does, you have a buyer (me) for your 14/19.....

 

[SurferSmurf]

if it does, you have a buyer (me) for your 14/19.....

im gonna make a phone call to skat or impros, unless supertune posts again with a suggested impeller. we can work out a deal then. ill keep ya posted.

 

[MADMAT]

If Smurf keeps his I have 2..... one -5mm 14/21 repitched to 14/19....and one regular 14/19.