SoCal Jet Boats

Discussion => The No Wake Zone => Topic started by: smoky03 on April 23, 2023, 09:10:23 PM

Title: impeller and rev limiter, new to jet boats, please be gentle.
Post by: smoky03 on April 23, 2023, 09:10:23 PM

hi, im buying a jet boat, here is the info below, im surious. it says it has a Blue print and balanced Impeller Bronze cut to a B.
i have no idea what this means. also its rev limiter is set to 4800, seems low to me.
a few questions.
why cut an impleller, why bronze and not stainless? and should i/ raise the rev limiter. im not sure what cams are in it yet but i will find out.
thank you all in advance!!
Big Block Chevy 454, Edelbrock manifold, edelbrock 750cfm carb, comp camshaft, comp cams hydraulic lifters, magnum rollers rockers,  Berkeley 12JG-A drive, Blue print and balanced Impeller Bronze cut to a B. 65 mph at the rev limiter set to 4800rpm. 1978 nordic

Title: Re: impeller and rev limiter, new to jet boats, please be gentle.
Post by: 96Laveycraft21Xt on April 24, 2023, 02:12:10 PM

Impellers are usually cut so that they bite less water and thereby run at a higher RPM for a given HP rating to match the RPM power curve of engine.  If the pump has a bronze B impeller then it was most likely set up for a different motor then what is in it now (my opinion) that is making way more power.

I decent built 454 should turn an "A" impeller 4800-5100 rpm all day long. 

Example off of the impeller chart, 4800 rpm with an A impeller is 350hp, the same HP with a B impeller is 5100 rpm.

It is possible they set the rev limiter to limit the top speed of the Boat. 



Very generic answer is YES,  most likely the rev limiter should be raised.  Long answer.... only you will know your driving ability and whether or not the limiter should be raised. 

Title: Re: impeller and rev limiter, new to jet boats, please be gentle.
Post by: 72 Nordic on April 27, 2023, 08:23:38 PM

What is this rev limiter you speak of? Foot, gas peddle, tach. The bare necessities. send it?


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