Whos got the impeller program?

[Danhercules]

By friend is having trouble. He had torn his pump apart a few times. He cannot understand the RPM's he is getting with the impeller cut he is getting. He says its not right. I think it is. I wanna plug some numbers. Can some one help me out?

[Danhercules]

My buddy is runnin a BBC, he is at 6k RPM, on a Aggressor B/C (witch he is telling me is a C/D berk cut, is this right?) at 73 MPH. His claims his HP is 631.
Dose this sound right?

[pops1]

My buddy is runnin a BBC, he is at 6k RPM, on a Aggressor B/C (witch he is telling me is a C/D berk cut, is this right?) at 73 MPH. His claims his HP is 631.
Dose this sound right? Yes, go one full cut smaller to get a Berkeley comp number.

[Squirtcha?]

Looks like you're right Dan. Ran the numbers and his hp comes out to 624.
Here's a link to Jet pump calculator (http://members.cox.net/lvjetboy/JPC.zip)

[dmontzsta]

631hp and 73mph? something is wrong.

[Squirtcha?]

It almost looks as though he could benefit from a larger cut, say maybe an B or AB (aggressor so we're comparing apples to apples).

[FHI-prez]

My buddy is runnin a BBC, he is at 6k RPM, on a Aggressor B/C (witch he is telling me is a C/D berk cut, is this right?) at 73 MPH. His claims his HP is 631.
Dose this sound right?
It goes the other way, an Aggressor B/C is comparable to a Berk A/B. The leading edge of the blade on an Aggressor goes all the way to the front of the wear ring surface. This in essance makes the blade longer which is why it's comparable to a larger Berk. A "B" cut Aggressor performs similar to an A Berk, but with arguably with a better hole shot. Hope this helps.
Nick

[SB]

Hey pops, who's on your computer?

[wet77]

It goes the other way, an Aggressor B/C is comparable to a Berk A/B. The leading edge of the blade on an Aggressor goes all the way to the front of the wear ring surface. This in essance makes the blade longer which is why it's comparable to a larger Berk. A "B" cut Aggressor performs similar to an A Berk, but with arguably with a better hole shot. Hope this helps.
Nick
Thats what I was told too my aggressor B bronze is compared to a Berkley A :D

[flat broke]

Dan,
I never saw any pics of how wet the boat was riding. Get him to post those up. I think drag is a big part of his problem. As for the program, PM LVjetboy, he wrote it and distributes it. And yes, for comparisson puposes, a Berk A would be like an Aggressor B. Here's the thing though. First your buddy should measure his impeller to see what he ACTUALLY has rather than spinin his wheels chasing a problem that might not exist.
Chris

[Danhercules]

Flat, look at the other thread. pics are up there. He has a diverter on there now.

[Nucking futs]

which thread Dan??? I want to see pics.......... :D

[Danhercules]

CBBB in the jets section.

[Squirtcha?]

Here's the picture. It looks like he could use some more up on the diverter. In the big picture (I cropped it some so's it would fit), it looks like he's got it in the center position (no rooster). It's riding a lot like my Kachina did before I did the bottom on it last winter. Buried................Actually he's got spray even further up the hull than mine did.
Was that a wide open pass Dan?
http://www.jetheaven.us/photopost/data/500/19joemechanik-med.jpg
http://www.jetheaven.us/photopost/data/500/19boat_ride.jpg

[rivertard]

Dan i run an aggressor b/c @ 6k,rpm got 83.4 mph.to much rpm.for my fords lower end. went to new aggressor a/b got 79.4@ 5400k. 565hp.going to cut on it somemore trying for 5700/5800 rpm.(rivertard). :messedup:

[FHI-prez]

BTW if he's got an Aggressor, the cut will be stamped on the back of the impeller along with the date it was made. Unless of course it's been modified since, so I guess this may not help at all. :D

[Bailey]

Is your buddys boat a Eliminator sprint? If so if he has 631 hp he should be going alot faster than that. Mine stock with about 250hp does 63 at 4800rpm.

[garret]

i have an agressor b cut turning 5300 rpm and couldnt get my computer to get to the jet pump calculator will somebody do the math

[Squirtcha?]

i have an agressor b cut turning 5300 rpm and couldnt get my computer to get to the jet pump calculator will somebody do the math
470

[Danhercules]

He did put on a diverter after those pics. But , the numbers I posted was with the diverter on the boat.

[JoeMekanik]

Ok, here's an update. Last out was a "c-d cut" as they call it. Its turning just shy of 6,000. With the diverter not fine tuned, it ran 73 mph on a new Magellan GPS. To answer the numerous inquries, the impellor is stamped a "aa Agressor" . This has been cut down, of course. The small diameter is 6-1/4". This is in my book a c-d berkeley cut , but a "b-c" Agressor. I think i'm going to ask to be referred to as " Witts end". Cause that's where i'm at.
Thanks for the help in advance, Joe.
P.S. sorry, can,t seem to figure out how to the j-peg images of the boat up.

[Squirtcha?]

It's difficult to tell without knowing the hp of the motor and at what rpm it comes in at, but you're turning a bunch of rpm for that 73 mph.
I've got less horsepower than you, (only 500 hp) and run 80 mph at 5300 rpm (Aggressor AB).
I said it earlier in this thread, and I'll reiterate............ I think you could benefit from a larger impeller. If nothing else, it'll save a bunch of wear and tear on your motor.
Just an opinion.