Not quite. I'm still waiting in his results. I'm skeptical. But, hopeful too. I've always liked the EWP, but won't ignore their limitations, especially where I live and what I'm building my car to do. If their was an EWP that was variable up to a TRUE 80 gpm and was reliable, I'd already have it. But none exists. He's doing a real world test in a bad realm of the EWP. If it's good for him in hot and dry conditions, I'll certainly jump on board. I honestly don't see it doing to well though.

 

there is no PH-9000 anywhere.

Dan

 

I gotta call bullshit on your statement regarding PH-9000. I went looking at various water pumps that I can be sure are original equipment and can't find PH-9000 on any of them.

What is consistent, however, is the casting number 10128327.

Where did you get your information?

I would concider running another pump along with this one, in series not parralell, but I can't find one not priced like gold.

Dan

 

Gah, I had it backwards. The casting number you have is right and I've also seen GM stamped into the lower right side of the housing. PH-9000 is a reproduction pump with unknown origin. I have one on my car although it is gutted for EWP, quality is alright. I know this pump went on in the early 2000s because my car came with service records when I bought it, guessing it's a later Delco pump being that it was repaired at a Chevy dealer. Some of the new parts store pumps don't have anything cast into them and are complete junk. A friend of mine was having problems with a hose barb falling out of the housing because it was poorly siliconed in. It was a Napa pump that got warrantied and the new one had the same issue out of the box. Also, not all of the new Delco pumps are created equal. The original design model is roughly twice the price.

Wouldn't it make more sense to run the pumps in parallel to boost the flow rate? The electric has a lesser flow rate than the mechanical starting at around 4k and beyond. That seems to be the biggest argument against the ewp.

 

Any water pump with PH-XXXX cast on it is an aftermarket pump from ASC.

 

This is pump rpm, not engine. Multiply engine rpm by 1.269 to get pump rpm.



You also have to assume that the EWP flow rates from Meziere, CSR, etc. account for pump head, but I've heard that's not the case. Did Meziere say anything about how the flow rating is measured?

 

Quote:

Originally Posted by LSXTV

Flowing anywhere from 20 to 36 gallons per minute (GPM) of coolant when installed, most electric water pumps can flow over three times what their mechanical counterparts are capable of at idle. “When we test a 55-gallon-per-minute-rated pump inside of a V8 system with a 17-by-22-inch” radiator we see about 22 gallons per minute, says Meziere.

Meziere him self stated that ALL his pumps are free flow rated and that all pumps SHOULD be free flow rated (for comparability reasons), but are not. As with the chart you provided (thanks!) those flow rates are as installed in the vehicle, with the engine, thermostat open and closed, radiator, etc. The LT1 pump flows 66 GPM at 6K pump rpms ~4700 engine RPMs, as installed. The Meziere HD flows 55GPM continuous free flow with zero resistance.

According to the chart provided and the information provided by Meziere, we see that by 2K engine RPMs the stock LT1 water pump and the Meziere 55GPM HD flow the same (if we installed a smaller radiator on to an F-Body that is, a larger one -like stock- will flow less). Beyond 2K the Mechanical flows more, a lot more as RPMs increase.

If you do a type of racing that keeps the engine rpms higher than that for extended periods of time, the mechanical pump is the better choice and will provide better cooling.

That is where the skepticism comes from. Not that they don't work. They do. But, they are limited in their ability to cool the engine down. And in certain environments and driving conditions are not the optimal choice. The EWP frees up HP by doing less. Whether your vehicle is o.k with the less work that the EWP provides is a different story.

If you look at that chart, you'll notice that a Meziere HD flows the same at 6K as the L98 with the thermostat CLOSED! Put that in perspective.

 

It has been said before that the LT1 water pump can begin to cavitate above 5k. Not sure how much truth there is to that. That graph came from a SAE doc (SAE 920673) which makes me wonder if there's any valuable info we're missing in there. I think it's really odd that the graph ends at 4700 engine RPM being that the LT1 in stock form goes for another 1k.

 

I've read that too, it doesn't surprise me. Not much can be done about that on the LT1 though.

 

Sure there is, you run a optimized impeller for high RPM window and a parallel EWP for idle to crossover point.

Money well wasted

 

Does anyone make a high RPM LT1 Mechanical water pump? If so, that could work with an inline EWP booster for low RPMs. But, as you stated, that sounds like a waste of money. Either pump will work fine so long as their application is correct. The EWP should be fine for 90% of us, if not more. Of course the mechanical should be fine for 100%.......

 

Nope! This is what we get for owning the bastard child of the SBC family.

 

55gpm meziere has to free up at least 10 crank hp. Im still getting one. Not many ppl stay over 5000rpm for long periods of time anyways. Hoping to keep idle temps low to add more timing with tune.

 

I have the regular ewp in my car.. It works just fine in the southern heat.. People are over thinking this whole ewp vs. mechanical debate.. If you need an ewp for timing chain reasons or for that last 5rwhp then get it.. If not stick with what you have.. They both work damn good at doing they're job..

 

The problem is that OP is building a circle track LT1 meaning high revs for extended periods of time.

I don't think the EWP vs mechanical argument is as one sided as gpm numbers. The radiator has to be taken into account as well being that it's the only way heat leaves your cooling system.

 

Agreed. That and air flow through the radiator too. I'd imagine the circle track cars have really good air flow too.

 

Can't see it on the dash BUT at a 75mph cruise the electrics allow the engine to run a few degrees warmer, so at a 75mph cruise the electrics are already beginning to lose control. On My Caprice in 40 degree temps the electric allowed the engine to run warmer at 75mph cruise, vs when it had the mechanical or even moments later at 35mph cruise, Not overheating but the fact the temp was elevated even in cool weather shows the ultimate capacity is reduced. Based on this is is only reasonable for the OP to conclude the as delivered electric will not work for him. Rather than accept that he is trying to improve the electric, I think he is wasting his effort, the electric pump motor is just too small. I will give him credit for not blindly believing the ignorance about how grand the electrics are with most people claiming they cool better while using less energy.

The electrics are sufficient for most uses, too many mistake that for "best for every use".

 

With the electric my car ran warmer at 75mp vs. 35mph even in cool weather, Caprice has pretty good airflow, generous amounts of space in front and back of the radiator. Circle track car is going to be more demanding than a Caprice at cruise.

 

Dwayne

since you say you can't notice a temp diff by the gauge with EWP vs mechanical at 75 mph in your Caprice, what method of temp measurement did you use to determine this?

data log??

FWIW I drive in conditions here in SoCal and Nevada where temps stay 110-115 quite a bit in summer. I also have lived in Wisconsin so I know how hot and cold it gets there. When I did the West Coast Gathering event in Vegas this year it was a 300+ mi drive through mostly desert with temps 115-118. At mostly 85 mph sustained , by gauge, my temps showed maybe a needles width higher than normal. My assumption is this was due more to the fact it was really hot and a EWP or mechanical would run slightly (whatever a needles width on the gauge amounts to) higher temp. My daily driver 4 cyl Ford also runs about a needles width on the gauge hotter in these conditions

We all know a EWP pump speed is constant so at lower RPMs it flows more than a mechanical and less at higher RPM's. The less at higher RPM's, for me, has not proved to be any cooling problem be it sustained (hours) 85 mph in 115+ degree heat, multiple back to back (aka hot lapping) 1/4 mi passes or general driving even in rush hr. In 17 years the EWP, again for me, has worked very well as a water pump.

My primary reason for swapping 17 years ago was due to the chronic weeping, and Opti damage, of mechanicals I was experiencing with dealer installed (under warranty) AC Delco new WP's. When my new car warranty expired and the then 500 mi new AC Delco was weeping I swapped to EWP. At close to 90k miles on my EWP now and 17 years it has lasted as long as what a mechanical should last in a properly maintained cooling system.

Not saying EWP is "better" than a mechanical. Just a alternate that for me has proven to be considerably better than mechanicals in terms of service life while providing adequate cooling for my car in the conditions I drive it in. Not debating on if it frees up HP or taxes the alternator output any more than a mechanical. Those threads have filled the forum for years.

I think the OP's attempts at modifying the Meziere for his use intent is admirable. Making "mods" to any component of the motor/car for track use is what all of us car enthusiasts favor. Hopefully his endeavor is successful but even if not attempting the mod is commendable.

For all the posts you have made criticizing the EWP I am glad to see you at least tried one. If it didn't work out for you the way you like, fine, and like me you can state your experience and opinion of the EWP. For me and many others the EWP has proven to work very well.

 

At .030, check for contact marks after a heat before starting a race. Thermal expansion rates will be different between the center of the pump and the outer housing. Hate to see the impeller stall from contact.



So with a decrease in coolant flow there is an increase in dwell time. More time for the coolant to absorb heat from the source as well as more time to release heat in its slower travel through the radiator. Is it out of the realm of possibility that what you have witnessed is the thermostat closing from excessive heat loss at highway speed?