Not any help to you, but when I hear jet boat, I think that it has a jet pump. But you keep emphasizing "retired". Does that mean that it had a jet engine with a jet pump? Otherwise, what does retired mean?

 

I'm asking because if you are trying to drive a massively oversized for your rpm pump, that would be pertinent info for choosing a cam.

 

Oh ok so retired as it has a Berkeley jet pump and I’m not ever going to race it. It had a 454 bored out crazy engine in it. I was given this boat and told to make sure the water cooled headers have enough water to keep them chrome. That night it rained so I wake up pull off the cover and it snagged on the valve to cool the headers. I was have more problems with the dual 4 barrels than anything. So it slipped my mind on that valve. I got it kinda running and started driving it. Well as soon as it got hot I had cotton candy coming out of the headers. It was my first time driving it so since we positioned that valve I thought it was normal. I start gunning it and I can hear a tick on the passenger side. Keep on going everything looks good I’m confused nothing gauge wise saying it doing something. That’s when my rear passenger says hey look. Water mixed with oil was coming from the timing cover, heads, oil dip stick everywhere. I was upset.

so it’s retired as I won’t be racing it water scares me I’ll have my truck to race on land. But I want to use this as a toy a reliable toy so the best this is a Ls

 

So worst case is that you won't have enough power to turn that pump to the new engine's power peak.

 

I understand that you don't care, but now my mind is clear, lol

 

Any engine can turn the pump it’s like bigger jet ski pump. I just want one that will have better sustained power rather than top end or bottom end. It’s how it runs through the powerband for me.

 

You will need power to a certain point tho. If the cam 5.3 doesn't have enough power it can still turn the pump but your boat speed will be limited. I've messed with some fan boats with LSs but never a jet boat tho. But same principal. Change prop or pitch vs impeller / pitch

 

Correct it will be limited to the rev limiter of the engine. With that in mind should I do anything to the pcm?

 

What pump and drive is in the boat?

 

​​​​​​​you will have to tune it for the cam