Tigerhawk

I'm considering an electric water pump when I replace the opti. Are they less reliable than a manual one? Do they stress the alternator? Also is the Dynaspark opti any better than a stock one? Thanks.

konroh

mine has been in for 2 summers...the only problem is when the relay failed, the temp shot up and luckily i saw it, pulled over, and shorted the wires together to turn the pump back on. no problems with the pump itself though.

Strick

The electric water pump (Meziere HD) is advertised to last at least 2500 hours. Do the math, it's longer than an OEM and it won't leak on your opti/Dyna spark when it goes. You also eliminate a possible oil leak from the gear driven shaft seal in the timing cover. One thing it is much easier to replace than the OEM pump, maybe 30 minutes and no gaskets to mess with. As far as alternator draw, it's 9amps. Most 92 -96 Vettes have at least a 120-140 amp alternator, I think. Any way, my system seems to handle it just fine. There are other advantages of having an electric pump; free up some HP, cooling after shutdown (nice at the track) and it is a constant flow not dependent on rpm which is great in traffic.

If you can, I'd suggest you go with the DynaSpark, it improves just about everything in the opticrap.

Here is how I did mine: https://www.corvetteforum.com/techti...=231&TopicID=2


[Modified by Strick, 12:05 PM 2/2/2004]

rick lambert

Electric vs. Mechanical, that almost answers the question doesn't it. :rolleyes:
Obviously there are some advantages-as mentioned, but in any case there are alot more possibilities of failure w/electrical :( Me-I'll stick w/mechanical. :seeya

62C1

I've had my Mezier pump for a little over a year and have been generally pleased. The pump did fail about 4 months after I installed it. One of the wires inside going to the brushes worked loose (they are secured inside by bedding them in RTV) and contacted the armature which wore throiugh it causing the pump to quit. Required a tow to get back. The fix was easy and the company helpful but I think the design could have been better. The other issue I found is that when running at speed and especially during track days the temp runs 10-15 degrees hotter. However when returning to idle the temp comes down quickly and I've never had it overheat in traffic. I have the standard duty pump installed and in hindsight I probably should have gotten the heavy duty pump which puts out more volume. The pump is great at autocrosses though. After a run I can leave the ignition on and the pump will circulate collant and cool the car right down. You also don't have the worry with the mechanical pump leaking and taking the opti out.

Z-PDX

This has always been an interesting question to me. And one I've never fully understood.

For an electric pump, you are turning mechanical energy (engine) into electrical energy (alternator) back into mechanical energy (DC pump).

So wouldn't a standard water pump be more efficient without the attendant losses in converting power along the way?

Or is the drag an alternator puts on an engine the same wether its at full load or zero load?

-Z

xs650

I believe I saw that the electric pumps mentioned are rated at 35 gpm when there is no resistance in the cooling system. That's not enough for sustained high power output, which is why you see your temps running higher when running at speed.

It doesn't overheat in traffic because on the average, you aren't using much horsepower power in traffic.

A decent performing Chevy small bloick should be running more like 80-100 gpm at full power.

With only 35 gpm flow through an engine putting out 300 hp, the coolant temp wil rise 40 to 50F on a single pass through the engine. If your radiator doesn't cool it back down 40 to 50 degrees, then you can't sustain that power without toasting your engine. That's on 100% water, the temperature change will be close to 80F if you are running 50/50 coolant. Radiators don't work very well when you are trying to get that much of a temperature drop out of them.

96GS#007

I have the heavy duty version of the Meziere which flows ~52gph. After 5,000 street miles and several hundred track miles I have yet to have an issue.

Upon install I ran 10* to 15* cooler on the track. I next added a Fluidyne radiator and dropped the temps a bit more. On an 80* to 85* day with typical midwestern humidity and dewpoints, my coolant temps have yet to exceed 220*. This is during extended track time with my rpms generally between 4000 & 6000 with frequent blasts to 6800. FWIW...

John Row

This kind of has a religious ferver to it. No one believes that the electric is more efficient. I don't remember who did it, but he had before/after dyno runs and the electric was 8-12HP better.

Corvette Kid

This thread just saved me from making a boo-boo! Saturday night I ordered a Meziere pump and figured I was alright with the standard duty because my engine isn't radical, no sustained high RPMs, etc. Also I figured why draw more current than necessary? But after reading this thread, I called them, it hadn't shipped yet due to computer problems and the guy upgraded me and wouldn't even accept the price difference, cool! Just told me to consider them again in the future. MASCperformance.com standard duty pump $202 shipped, heavy duty $209 shipped. :thumbs:

FD2BLK

I can't speak to longevity but the HD Miezer runs cooler then the OEM W/P and uses LESS HP. I know because I have been running one for over a year with Zero problems. I installed the warning LEDs so I would know if I had a power or ground fault and would recomend anyone running the electric W/P do the same it was less then $15 in parts from Radio Shack. I always get a kick out of the amount of people who have never run or tested an electric W/P saying they are unreliable or they wont cool as well as the OEM unit. Look at the results of the people who use them and you can see that they are very reliable and cool better then the OEM unit and wont trash your opti when tey do die. The HD unit is a better choice for the couple of extra bucks and that is what most people get. I have also seen good results from my F-body friends running the CSI unit but it is a little more work to install because the case needs to moded quite a bit to make the pump fit corectly.

John Row

Warning: Be sure to use a 30amp (or better) relay. I had 3 20amp units go out. Each lasted about 4-6 months. The 30amp Bosch has been running for about a year now.

BTW: I keep a spare relay in the well behind the passenger seat.


I can't say enough about the folks at Meziere. I was having a problem (turned out to be a bad relay). Meziere is just a few miles from me, so I took the pump to them to test it. They had an engineer run tests on it for about 2 hours while I waited. Nothing wrong with the pump. They said they had improved brushes and did I want them to upgrade it. So, they tore it apart, replaced the brushes and ran 2 more hours of testing. No charge! Mrs. Meziere (the mom) came by to see if I was being taken care of!



[Modified by John Row, 8:43 AM 2/3/2004]

xs650

You temps would be interesting if you decided to run in hot weather.

96GS#007

They were fine on two 101* days last August here in St. Louis at Gateway International. The air was so thick you could swim thru it. Asphault temps were ~140* Coolant temps never exceeded 230*



[Modified by 96GS#007, 2:16 PM 2/3/2004]

Strick

Here is something to think about, your cooling fans are electric, not mechanical. Are they less reliable? No, if anything they are more reliable.

nonetooclose

Cooling fans have almost no perceptable load unlike a water pump. Not a good analogy. The electric will prove to be more efficient due to it not drawing full power constantly, that is if it is controlled appropriately. Does the pump actually fluctuate pumping? Variable pumping?

If not then the previous post regarding efficiency is correct and it really does not benefit in the long run. On the flipside, when you are screaming down the track for a 1/4 mile run you do not want any parasitic losses. In this case one could potentially just turn off the pump. Just food for thought.

One advantage with electric is that you could have it cool the vehicle after it is shut off. Reduces chances of late boilover.

Thanks
Richard

John Row

The Meziere HD is constant speed 10amp draw.

A mechanical pump is only efficient at a very small RPM range. Above that range it will cavitate, continue to drawn more power and not pump as much water.

An electric pump can be made to run at very high efficiency at a single RPM.

xs650

You are off base on mechanical pumps. unfortunately the comparisons here have all been the lousy efficiency stock pumps vs an optimized big $$$ aftermarket electric pump. Compare the electric pumps with equally high quality aftermarket mechanical pumps and the difference is much smaller.

Ramrod92

Dick, where have you found an "high quality aftermarket mechanical pump" for a LTx engine? Both my stock GM units didn't even make it to 50,000. The Last Detail has the Delco for $183 and a repro for $160. I got the HD Meziere for $210. I have to agree that the Meziere is an "optimized" pump, but I certainly wouldn't call it "high dollar". And here for your viewing pleasure is the back of my 2nd GM unit with 48,000 on it. Here's the front of the Meziere :thumbs:

Strick

I think the anology is a good one when talking about reliablity. For years, cooling fans have been mechanical as the water pumps have. Then the movement went to electric fans and they found them to be more efficent, reliable and produce less engine drag. Now, we're finding the electric water pump is more efficent, reliable and produces less engine drag. And it is easier to replace than a mechanical pump at least on the LT1/4. I see in the future, electric pumps being controlled by the ECM for optimum flow rates at different RPM ranges as well as cooling demands after a high engine demand. Enough of my "crystal ball" viewing. :skep: