The conical shape of the stock water pump blades seems to be normal. Meziere, and others, rate their pumps NOT on the engine or with the radiator, etc. In other words the impeller is not designed specifically for the LT1 water pump. So it's not surprising to see that it's shape doesn't follow the contours of the stock OEM unit.

GM realized what you do, clearance between the impeller and the housing has a direct effect on the impellers ability to move water, so they made the impellers conical to match the housing. I'm sure this is something Meziere knows too, but likely they don't have the money (unlike GM, who also used a different process) to justify manufacturing conically shaped impellers for all the different water pumps this impeller may be used in (likely not many as most are not conical in shape like the LT1 is).

But, even with that most (damn near all) EWP reviews I have seen show no signs of overheating due to pumping deficiencies for MOST scenarios. That is to say, the clearance issue you speak of obviously had little effect on MOST peoples builds.

But, you are NOT most people. You want to install this on a vehicle that will likely see more than 5K rpms consistently for long periods of times at a relatively low speed. In damn near all applications that an EWP has been used for similar set ups, those guys report uncomfortably high coolant temps (but no one said they overheated; to be fair here, they also let off).

So, I'm in for the results (especially summer time heat results). I'm interested to see how this works out for you. That is probably the worst situation to put an EWP and if it works for you, I'll buy one! Seriously. I've always liked the EWP, but they are all under powered (except for BMW's, but they are not as reliable). I've always been suspicious of the EWP limits, maybe you can prove my suspicions wrong. I remain skeptical though.

Anymore info on your build?

 

I don't see this conical aspect?

And wide tolerances are a fact of life with a mass produced crappy casting, then adding in a stamped steel impellor, yea gonna be loose clearances.

Either way, you have the info you need, def please post back up with results.

 

On the aft side of the stock impeller you can see the outboard edge is thinner then the inboard edge of each impeller blade. Also on the stock housing it's the same way, to match the impeller blades. The EWP impeller doesn't have that. That will increase the clearance between the EWP impeller and water pump housing (bad). The stock set up actually has tighter tolerances than the EWP set up. This doesn't seem to present any issues with many users though. Although in his intended use of it, it can be.

 

Ah, the taper of each blade, ok I can see that, wouldn't call it conical though

Still wouldn't worry about clearances, but we are gonna dive down the rabbit hole of thinking about how the OEM engineer thought 25 years ago.

 

It's conical when you consider all blades together given their orientation to eachother. It's an accurate description, but taper of each blade works too I guess.

 

I didn't know to be curious about the stock impeller axial clearance and the bearing was shot anyway so trying to measure it would have been futile.

The very closest the Meziere impeller gets to the housing as delivered is .135". That's more than an eighth of an inch and a giant leak path around the edges (sides) of the blades.

Personally I would be concerned about that no matter what the application.

The Mezerie impeller looks to be machined from a billet and it just seems like a program could be written for the machine specifically for the LT1.

It just occurred to me that maybe I got a pump with an impeller intended for another application. I'll call them and get back with the results.

Dan

 

.135 is huge. Maybe you're right and you got a different impeller set up.

 

Just got off the phone with someone ( didn't get his name) who was aware of the mis-match and couldn't offer an explanation but promised to run it by engineering to see why. He assured me that I have the correct impeller for the LT1.

He did mention that some of the MOPAR applications are shaped other than flat out of necessity but didn't elaborate.

I'll get back when I hear something.

Dan

 

Kudos to Greg at Meziere for getting back to me right away. He talks straight up.

Something I hadn't noticed is that the LT1 pump turns backward compared to all the rest so experimenting with another model impeller is out. The passages in the casting are directional.

The EWP I have is the only one for the LT1. I was told that when the Lt1 first came out they tried a backwards turning version of an existing model and it worked so well they didn't test further.

He mentioned their model WP105 which is for a BB MOPAR has a back wall built into the impeller because the MOPAR pump castings were so inconsistant and the clearance varied so much.

He also agreed that I'm on the right track for, my application, in looking to reduce the clearance and thought the motor was up to any additional load I could put to it.

Business is calling me away from the project for several days so I won't be getting started right away. When I've got something to show I'll be back to this thread.

Dan
Dan

 

I don't think it would be too difficult to measure/reverse engineer the current impeller then add material in the areas you want it to close the clearance gap. Send it to a machine shop and voila!

This is assuming you have access to a solid modeling program, caliper, height gauge, and a machine shop lol.

 

I would weld up the conical area of the pump housing then machine it down flat to the desired clearance (.040) from the impeller.

 

Sorry it took so long to get back. I added a couple of more images to the http://imgur.com/a/kpQmY album.

Was afraid to try welding down in the cavity because if it slobbered outward it would be hard to remove. I'm a guy who can make stuff for myself with machinery, but I'm not a machinist. And I haven't TIG welded in a couple of years so I'm rusty.

What I did was to machine the conical surface flat with a step to center a spacer I made that has a corresponding step.

I stuck the spacer in with JB weld and then drilled and tapped around the edge for some 10-24 set screws that were JB welded in so that they traversed through both the casting and the spacer, just for assurance.

I also removed the center, raised, part of the casting that held the original bearing, figuring it would leave more room for circulation, and then plugged all the unused holes with weld.

The season is over till March so I won't get to try it till then, I'll see if I can get back to this thread at that time with a report.

Thanks for your input,

Dan

 

Nice work. I'm interested to see how the EWP holds up for you with your style of racing. If it does well, depending on how your ambient conditions are to mine), I'll be installing an EWP too.

 

Why the change of heart? IIRC the multiple posts of you arguing your opinion made it seem you were pretty dead set in staying with the mechanical pump.

 

Is it the original wp housing or a autozone china made wp housing that the meziere ewp is trying to fit into, that could make a fitment difference? EWP free's up hp on a Lt1 period. It runs on a small amount of electricity from the alternator. According to non believers, when you run your headlights you must lose 10hp then?

 

I didn't attempt to get the casting number in the pics but it is readable in one pic, and googles to a GM water pump part. I got the pump used so I have no history on it.

My phone conversation with Meziere revealed that they are aware of the misfit but in their testing found it to be acceptable for their advertised purpose, as many have attested to.

My purpose is more demanding and that's why I'm taking these steps.

I forgot to mention earlier that I faced the spacer and the pump mount surface in the same setup to a clearance of .030". We'll see.

Dan

 

No change of heart here. If you actually read what I said you'll understand my position.

 

That's not what was stated. Period.

 

Edit: PH-9000 is a reproduction pump.

Ever consider running a second remote pump in parallel?

 

right. it wasn't right for you, lots of opinion as to why, and now it is. funny how that works out.