How much are you looking to spend?

What kind of hull? 18-19’ lo profile or 21’ cruiser?
How much HP will your new motor have? A stronger impeller is probably recommend around 550-600 hp. Even higher hp than that, an AQ shaft is an consideration. A pump blueprint should be considered just to make it more efficient. At what RPM are you looking to make this power? Jet boat motors are built to find that sweet spot with the impeller. When you add more power, you also have to make sure the pump stays loaded with water. It might be as easy as adding a loader.
D1 Performance was in Rancho Cucamunga. I’m not sure if he’s still in the business.
GS Marine is down the 15 in Norco.
Cyclone Speed and Marine is in Pacoima. Jim Brock is a member here.
Jet Boat Performance in Atascadero. It’s far but, Tom and Josh have always been very helpful.
Don’t let this scare you off though. Your boat might run fine as is. These are just some things that might need to be considered to make it run better. It would suck to have a nice healthy motor built and notice little difference because your pump can’t transfer the HP to thrust.
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