im asking because i dont know... Impeller question

« **on:** February 11, 2015, 08:45:44 AM »

Hi All,

Im new to jets, i understand the theory and how they work. Thats all good and dandy, and i somewhat understand Impeller sizing and the effect that has.

Heres my question to the SCJB community;

I have a JC pump that i bought off of another member here. Its in decent shape but needs to be freshened up. Im buying an impeller and wear ring (and most liekly everything else) off of GT here.
Now i know that the impeller and wear ring i am buying from GT will be matched to eachother. and should fit no problem.

My wquestion is if i were to take another "A" impeller i have and have it cut down to a B or so, could i simply swap these out? Or do i have to have it machined to fit that wear ring? Is it like a prop where i can just swap it out? Im assuming no...

Thanks!

« **Reply #1 on:** February 11, 2015, 09:01:17 AM »

Quote from: steves86ta on February 11, 2015, 08:45:44 AM

Hi All,

Im new to jets, i understand the theory and how they work. Thats all good and dandy, and i somewhat understand Impeller sizing and the effect that has.

Heres my question to the SCJB community;

I have a JC pump that i bought off of another member here. Its in decent shape but needs to be freshened up. Im buying an impeller and wear ring (and most liekly everything else) off of GT here.
Now i know that the impeller and wear ring i am buying from GT will be matched to eachother. and should fit no problem.

My wquestion is if i were to take another "A" impeller i have and have it cut down to a B or so, could i simply swap these out? Or do i have to have it machined to fit that wear ring? Is it like a prop where i can just swap it out? Im assuming no...

Thanks!

First question.

Why would you want to cut down to a B?

To answer your question, sure. You could simply swap one impeller out for another. As long as the wear ring is .024" to .030" larger than the other impeller.

As you may already know, you can buy undersized wear rings and cut the impeller down. not too tough to do, just requires a large throw lathe and some basic skills.

Good hunting.

GT

Sent from my SCH-I545 using SoCal Jet Boats mobile app

« **Reply #2 on:** February 11, 2015, 09:05:20 AM »

Quote from: GT Jets on February 11, 2015, 09:01:17 AM

First question.

Why would you want to cut down to a B?

To answer your question, sure. You could simply swap one impeller out for another. As long as the wear ring is .024" to .030" larger than the other impeller.

As you may already know, you can buy undersized wear rings and cut the impeller down. not too tough to do, just requires a large throw lathe and some basic skills.

Good hunting.

GT

Sent from my SCH-I545 using SoCal Jet Boats mobile app

Hey GT,

Thanks for getting back to my post.

Im just thinking while i have an extra one laying around i can have it cut down and experiment. (assuming its not like 500 to have one cut) PLUS my LS will not make peak power until around the 6k mark. I dont see swinging an A to 6k with approk 550 hp but we will see. It was literally for experimental purposes.

thnaks

« **Reply #3 on:** February 11, 2015, 09:11:04 AM »

Quote from: steves86ta on February 11, 2015, 09:05:20 AM

Hey GT,

Thanks for getting back to my post.

Im just thinking while i have an extra one laying around i can have it cut down and experiment. (assuming its not like 500 to have one cut) PLUS my LS will not make peak power until around the 6k mark. I dont see swinging an A to 6k with approk 550 hp but we will see. It was literally for experimental purposes.

thnaks

You will want to keep it at our near 5,500, peak torque on an LS us pretty high, but peak power is different math. I'm thinking you will be able to rock an A with little drama. Maybe an AB if anything.

GT

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« **Reply #4 on:** February 11, 2015, 09:12:43 AM »

It costs about $70 to cut an aluminum down a step. $100 for a mag bronze, $140 for a stainless.

See ya.

GT

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« **Reply #5 on:** February 11, 2015, 09:13:09 AM »

Quote from: GT Jets on February 11, 2015, 09:11:04 AM

You will want to keep it at our near 5,500, peak torque on an LS us pretty high, but peak power is different math. I'm thinking you will be able to rock an A with little drama. Maybe an AB if anything.

GT

Sent from my SCH-I545 using SoCal Jet Boats mobile app

sounds good, from what ive been told by the cam manufacturer, Torque should come on real strong right around 3500-4k and should pull real hard and flat to 6-6500.

« **Reply #6 on:** February 11, 2015, 09:16:00 AM »

Quote from: steves86ta on February 11, 2015, 09:13:09 AM

sounds good, from what ive been told by the cam manufacturer, Torque should come on real strong right around 3500-4k and should pull real hard and flat to 6-6500.

You need to look at an impeller chart. A Ford four cylinder can pull to 4,000 rpm. ...

GT

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« **Reply #7 on:** February 11, 2015, 09:19:23 AM »

Quote from: GT Jets on February 11, 2015, 09:16:00 AM

You need to look at an impeller chart. A Ford four cylinder can pull to 4,000 rpm. ...

GT

Sent from my SCH-I545 using SoCal Jet Boats mobile app

i did, thats what made me confused?

According to this chart, with the horspower i think im going to be at it says an A for 5500, but a C for 6K. is there a rule of thumb on how many rpm you want to swing a jet? Maybe somewhere it loses efficiency?

« **Reply #8 on:** February 11, 2015, 09:23:07 AM »

Quote from: steves86ta on February 11, 2015, 09:19:23 AM

i did, thats what made me confused?

According to this chart, with the horspower i think im going to be at it says an A for 5500, but a C for 6K. is there a rule of thumb on how many rpm you want to swing a jet? Maybe somewhere it loses efficiency?

« **Reply #9 on:** February 11, 2015, 10:47:40 AM »

Quote from: steves86ta on February 11, 2015, 09:19:23 AM

i did, thats what made me confused?

According to this chart, with the horspower i think im going to be at it says an A for 5500, but a C for 6K. is there a rule of thumb on how many rpm you want to swing a jet? Maybe somewhere it loses efficiency?

Do you know what the hp is at 5,500?

Do you know where max torque is made and where the lines cross?

GT

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« **Reply #10 on:** February 11, 2015, 10:50:48 AM »

Quote from: GT Jets on February 11, 2015, 10:47:40 AM

Do you know what the hp is at 5,500?

Do you know where max torque is made and where the lines cross?

GT

Sent from my SM-G900V using SoCal Jet Boats mobile app

Purely guessing at this point, based on what cars are doing with this combination.

The more i think about it, the more i think ill just run the A impeller, and see how it actually performs. After that then i can make a determination on what size impeller to go for

« **Reply #11 on:** February 11, 2015, 10:52:44 AM »

Quote from: steves86ta on February 11, 2015, 10:50:48 AM

Purely guessing at this point, based on what cars are doing with this combination.

The more i think about it, the more i think ill just run the A impeller, and see how it actually performs. After that then i can make a determination on what size impeller to go for

That is what I would do. Without a good dyno sheet, it's throwing darts.

GT

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« **Reply #12 on:** February 11, 2015, 10:53:50 AM »

Quote from: GT Jets on February 11, 2015, 10:52:44 AM

That is what I would do. Without a good dyno sheet, it's throwing darts.

GT

Sent from my SM-G900V using SoCal Jet Boats mobile app

Yeah, and since Westech wants 800 to run an engine on a dyno ill pass... haha

steves86ta

im asking because i dont know... Impeller question

GT Jets

Re: im asking because i dont know... Impeller question

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Re: im asking because i dont know... Impeller question

GT Jets

Re: im asking because i dont know... Impeller question

GT Jets

Re: im asking because i dont know... Impeller question

steves86ta

Re: im asking because i dont know... Impeller question

GT Jets

Re: im asking because i dont know... Impeller question

steves86ta

Re: im asking because i dont know... Impeller question

steves86ta

Re: im asking because i dont know... Impeller question

GT Jets

Re: im asking because i dont know... Impeller question

steves86ta

Re: im asking because i dont know... Impeller question

GT Jets

Re: im asking because i dont know... Impeller question

steves86ta

Re: im asking because i dont know... Impeller question