Pump Size vs Engine Power

[brapperdoodle]

Do you "need" a certain amount of power to really benefit from a 148 pump? Im interested in upgrading my jet pump but im not trying to build a crazy powerful engine. What would make you choose a 144 pump over 148 pump?

 

[Quinc]

148 will compliment any engine.

 

[Storbeck]

From a purely pragmatic perspective, 144 impellers are usually less expensive and/or easier to find used, if a guy wants to try multiple impellers while tuning.

 

[Big Kahuna]

I ran a 148 torrent with a ported 735

 

[brapperdoodle]

Awesome! So it’s that simple. A larger pump will always move more volume of water regardless of input power. Well 148 it is then

 

[wmazz]

A larger pump will always move more volume of water regardless of input power.

This is a subject that I know little to nothing about? Why will a larger pump
move more water when they require smaller pitch impellers.

I do know that when the pump is inefficient, it is possible to increase acceleration,
and that oem pumps don't always fill evenly.

But no mater what size the pump is, horsepower and pump load reach an equilibrium
when the pump becomes efficient. I really don't know, but to me that implies that
some different combination of impeller and nozzle will process approximately the
same amount of water ?????? @WOT due to the equilibrium.

The only thing that kinda makes sense, is at PJS we used to believe that an increased
nozzle diameter was something like increasing traction with a wider tire. I can see
how that might work while accelerating (when the pump is inefficient), but I am not
sure about WOT when the pump is efficient.


Bill M.

 

[Big Kahuna]

Awesome! So it’s that simple. A larger pump will always move more volume of water regardless of input power. Well 148 it is then

errrrrrrrrrrr, Not if you have the wrong prop.

 

[Christian_83]

155 will compliment any engine 155 pump deffo seems to be the pump with the widest sweet spot.
Yamaha used the 155 in stock 701 and 760 i couches. They work great for feestyle/freeride setups.

 

[CARBONX2]

Bigger pumps allow a lower angle on blades so they cut through the water more easily while moving the same amount of water as higher pitch in a smaller pump.

 

[brapperdoodle]

errrrrrrrrrrr, Not if you have the wrong prop.

Can you point me to information on how to select the correct prop? I’m sure it varies with what you want and where you’re trying to ride.