lol yeah no kidding!

i like the fuel economy of the small blocks. because im a cheap bastard

Lol, ya, cuz you get kick ass gas mileage hitting that nos button.

Seriously though. I've been told by a couple people that put some serious HP to their aluminum impellers they can last

Just depends on how you treat it. Mainly keeping the pump hooked. Try not to shock load it by coming out of the water.

I'd imagine yours should last longer than mine being hit with the nitrous. It's an instant 1k rpm when it hits.

I try my hardest to not come out of the water, and if I do I try my hardest to lift off the throttle before it hits the water again

I call bullshit on the serious hp, it's simply a matter of luck and time.

Been lucky and running out of time.

I have scattered two aluminum Berkeley impellers on nothing but RPM and horsepower. It destroys more than just the impeller btw.

GT

 IMO, its a crap shoot with aluminum and high HP.  I cracked a brand new aluminum with about 500 HP (cracked one "blade" at the hub with no mark from it hitting anything) replaced with another one and never had a problem after that.  I got lucky and saw the crack while checking the loader before it got too bad and came apart.  You might get a good one that will take it, and you might not. Is it worth the risk to YOU, that's the question. 

that was what i was thinking about.... since its going to be more than a little while before i can start ordering parts. I figured it woul give me something to do.


Let me ask another question. Since in my application my cleanout is not usable. Would it be worth it having it welded/capped off?

 I wouldn't worry about it.  With the exemption of a good/properly set up loader, your best investment in time or money will be behind the suction housing.  If you weld it shut, what about when you want to swap your good pump into another hull someday where it would be useable, or you want a pop off valve ?  Some places use to sell a "tight fit" cleanout cover, kinda like what I made. If your worried about it you might try finding one of those.  That way its still removable (like mine) if someday you need it, and you don't ruin a good suction housing.

 If you really need something to do...... Grab a sawzall and cut all the "extra" weight you can find out of the boat.  It will help more than messin with the suction housing.

 If you still have any doubts, I'm sure GT will be along shortly to help explain how much time and effort I wasted in that suction housing. LOL  But it looks cool. 

lol. I cant afford to be on the list

U can do it


Sent from my iPhone using SoCal Jet Boats

So as I'm reading through this interesting thread I click the link to the CP shaft and bearing kit for $600.

I bought a hardened shaft from our local Jet expert's shop for $1000 I believe a couple of years ago.

Then I bought the high end Inducer from him, HCM comes to mind, for $450.

I got what I wanted and was happy to spend the money with this guy. I won't mention his name cause the last thing I want to do is throw him under the bus.

Somebody tell me what I got is way better than the CP stuff 

I also have a quality Stainless HTP Hi Helix impeller race tuned by Duane, very happy with the $1250 spent.

B1 Loader $300

Then there's everything on the outside, bowl, PD ...

Damn this crap is expensive. I buy 1 piece at a time and try not to think about the total spent.

Flying across the water full grin, so worth it! 

I hope its not better. I'd be pissed lol

Heres another picture from CP's site. Looks like a DPS inducer

An "AQ shaft" is an abbreviation for the trade name Aquamet, a proprietary alloy, which was the first high-strength marine prop shaft material produced.  17-4 stainless has similar mechanical properties to Aquamet, but was not commercially available until some time after.  Performance shafts started being produced from the much more economical 17-4 SS, however the "AQ shaft" name had stuck.

You can read about Aquamet at http://www.aquamet.com/gradecomparison.nxg

When someone says "AQ shaft," what they mean is a high-performance shaft of usually 17-4 stainless, but it could also be the real deal, however rare that may be.

You can tell if you have the good shaft by if a magnet sticks to it.  17-4 stainless steel is magnetic.

Steve,

Now I am seeing the whole picture.  Been a little overwhelmed at work and it's hard for me to keep track of what everyone is doing.

GT is absolutely spot on when he said machining the front of the hub is killing the water flow.  The water flow just can't recover from crashing into the huge wall that was created by cutting the front of the hub off.  As the water is deflected off, a large portion of the blades are shadowed from water flow.

The only way you can save that impeller is to machine and hand detail the transition between the shaft and the hub.

I now believe what you are experiencing is a combination of pluses and minuses.  You change the cut size, the leakage through the wear ring clearance, and you change the turbulence generated at the inlet eye of the impeller.  All of these things affect pump performance and you are not getting a true apples to apples comparison.

I wouldn't waste any $ on postage to ship that impeller to AT.  What the guy at American Turbine said about the cross-section area and flow might normally be a factor, however, in this case it is not.  You can see what the guy at American Turbine is talking about when you look at the cut-away pictures of their pumps showing the venturi shape.  This all-important venturi shape starts with a large area in the suction housing in front of the inlet eye of the impeller.  The cross-section quickly reduces in the impeller and continues into the bowl.  Then the cross-sectional area expands again, right before the droop.

What happens inside the pump is, the water is mechanically accelerated by the impeller.  The water is at a high-velocity, but at a relatively low pressure.  The expansion of the cross-section area right before the droop causes the water to slow, but the energy is converted into pressure before the final restriction of the nozzle.