E water pump on FI
Burning Brakes
Joined: Aug 2002
Posts: 949
Likes: 1
From: Cary Il
Mezzier 55 gpm working GREAT for 3 years - Needed it for "Staging Lane Heat Mgmnt." Its wired to the ignition. Also have a fan relay ground switch so I can run the Spal fans at will. With all my electronics (KB BAP, Magna Fuel Pump, Fast WB, AM Backup Tach, 2 Pod Gauges, Radio, etc.) and the lights on I need 92 Amps. hot. Start up cold, lights off 63 Amps.
Former Vendor
Joined: May 2005
Posts: 3,749
Likes: 4
From: Valencia Ca
They don't last very long, nowhere close to their mechanical counterparts. Also, they don't give any warning when they die, they will suddenly take a dump, leaving you at the side of the road. They definitely make sense for a trailered track car, but not for my daily driver.
...and the big downside is flow rates and volume, especially at high RPM
Race Director
Joined: Apr 2005
Posts: 10,179
Likes: 2,306
From: Wesley Chapel, FL Las Vegas, NV
Obviously a mechanical pump will flow higher rates at high rpm compared to low but the radiator can only cool a certain volume.
Higher flow does not necessarily equate to cooler temps.
The faster the coolant passes through the radiator the less heat is taken out. So it's also a matter of determining the optimum flow to maximize cooling.
Also the flow is restricted at the t-stat so at a some point the volume does not continue to increase buy the pressure in the block will.
Last edited by Vega$Vette; Jun 29, 2008 at 08:35 PM.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
Back to back runs with my Maggie at high rpms I have never seen any spikes in coolant temps.
Obviously a mechanical pump will flow higher rates at high rpm compared to low but the radiator can only cool a certain volume.
Higher flow does not necessarily equate to cooler temps.
The faster the coolant passes through the radiator the less heat is taken out. So it's also a matter of determining the optimum flow to maximize cooling.
Also the flow is restricted at the t-stat so at a some point the volume does not continue to increase buy the pressure in the block will.
Obviously a mechanical pump will flow higher rates at high rpm compared to low but the radiator can only cool a certain volume.
Higher flow does not necessarily equate to cooler temps.
The faster the coolant passes through the radiator the less heat is taken out. So it's also a matter of determining the optimum flow to maximize cooling.
Also the flow is restricted at the t-stat so at a some point the volume does not continue to increase buy the pressure in the block will.
I have experienced the issue of a high volume pump inadequately cooling on an old Chevy smallblock with factory radiator. I switched back to OEM replacement and operating temps were down as before the "more is better" swap. In some cases more is better, but as we all have experienced, higher performance needs matched components to truly perform. I just cannot see that a high volume water pump is "snakeoil" for as long as they have been in existance, everything has it's proper application
Race Director
Joined: Apr 2005
Posts: 10,179
Likes: 2,306
From: Wesley Chapel, FL Las Vegas, NV
Maybe the key here is sustained high rpm's moving a higher volume of water that can be cooled better with higher velocity windspeed through a high performance radiator core on a roadcourse. Another consideration with the Evans unit is their coolant and how they claim it differs from standard Prestone or Dexcool.
I have experienced the issue of a high volume pump inadequately cooling on an old Chevy smallblock with factory radiator. I switched back to OEM replacement and operating temps were down as before the "more is better" swap. In some cases more is better, but as we all have experienced, higher performance needs matched components to truly perform. I just cannot see that a high volume water pump is "snakeoil" for as long as they have been in existance, everything has it's proper application
I have experienced the issue of a high volume pump inadequately cooling on an old Chevy smallblock with factory radiator. I switched back to OEM replacement and operating temps were down as before the "more is better" swap. In some cases more is better, but as we all have experienced, higher performance needs matched components to truly perform. I just cannot see that a high volume water pump is "snakeoil" for as long as they have been in existance, everything has it's proper application
The best coolant is 100% distilled water. Some people believe running a higher percentage of Dexcool will yield lower temps. Coolant mixes are only for corrosion resistance and to protect against freezing.
I run 30 Dexcool to 70 distilled water.
Former Vendor
Joined: May 2005
Posts: 3,749
Likes: 4
From: Valencia Ca
Testing by Evans shows that we need 55 GPM at high RPM or sustained high loads to adequately cool our motors.....especially critical in the back cylinders - No's 7&8
E-pumps are presently providing 25 GPM - who knows, maybe someone will introduce a BLDC e-pump that can increase RPM/Flow through feedback from throttle position, ECT's, MAP, etc..
Using an Evans mechanical pump in conjunction with a Dewitt or other similar radiator is my recommendation.
E-pumps are presently providing 25 GPM - who knows, maybe someone will introduce a BLDC e-pump that can increase RPM/Flow through feedback from throttle position, ECT's, MAP, etc..
Using an Evans mechanical pump in conjunction with a Dewitt or other similar radiator is my recommendation.
Race Director
Joined: Apr 2005
Posts: 10,179
Likes: 2,306
From: Wesley Chapel, FL Las Vegas, NV
Testing by Evans shows that we need 55 GPM at high RPM or sustained high loads to adequately cool our motors.....especially critical in the back cylinders - No's 7&8
E-pumps are presently providing 25 GPM - who knows, maybe someone will introduce a BLDC e-pump that can increase RPM/Flow through feedback from throttle position, ECT's, MAP, etc..
Using an Evans mechanical pump in conjunction with a Dewitt or other similar radiator is my recommendation.
E-pumps are presently providing 25 GPM - who knows, maybe someone will introduce a BLDC e-pump that can increase RPM/Flow through feedback from throttle position, ECT's, MAP, etc..
Using an Evans mechanical pump in conjunction with a Dewitt or other similar radiator is my recommendation.
Thanks
Le Mans Master
Joined: Jan 2006
Posts: 6,831
Likes: 4
From: Vacaville Ca
St. Jude Donor '13
Interesting thread, I had heard mechanical water pumps cannot be built to funtion well at both high rpm and low rpm because if the vanes of the pump are agressive enough to pump well at low rpm they will cavitate at high rpm. They will be trying to take such a big bite of water they will leave a void behind them, a pocket that will be empty bite for the next vane. If you built it to perform well at High RPM it will not work well at low rpm, not move enough water. That's when E pumps started to make sense to me. I know by the end of the 1/4 mile I have increased temps but it quickly cools back down on the return road...
Great thread
Steve
Great thread
Steve
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Safety Car
Joined: Apr 2004
Posts: 3,932
Likes: 8
From: Hayward California
Assuming good optimal airflow management, evans pump and big radiator is as good as it gets... it would be optimal, anything else would be less for folks who could benefit from it. Driving in the street and the occasional strip, it'll be "fine". 
Premium Supporting Vendor
Joined: Oct 2004
Posts: 23,599
Likes: 1,225
From: Providing the most proven supercharger kits for your C5/6/7 609-752-0321
We generally only recommend them for the drag guys, nothing better than being able to leave the WP and coolant fans on while sitting in the staging lanes.
I also have one on my own car for this purpose, and have no issue's on the street, but I have not found it necessary for the average guy.
I also have one on my own car for this purpose, and have no issue's on the street, but I have not found it necessary for the average guy.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
FYI, the Meziere WP for the LS family of engines flows a constant 55gpm as mentioned in the link below. The Evans mechanical pump addresses the high rpm cavitation issue with their own special mix designed specifically for their "system"
http://www.meziere.com/displaycatego...44,332,358,388
http://www.evanscooling.com/index2.html
http://www.meziere.com/displaycatego...44,332,358,388
http://www.evanscooling.com/index2.html
Melting Slicks
Joined: Dec 2000
Posts: 2,118
Likes: 2
I have had an Evans pump and NPG+ coolant for over 2 years....never an overheating issue. Even on hot 100+ degree days the highest temp ever seen is 217....usually run in the 165 to 183 range on hot days when cruising.Call Steve Prestley at Evans for the bypass mod.....it increases flow. The Evans NPG+ has a much higher flash point than water and carries more heat away. Its much better than any water combo.
Race Director
Joined: Apr 2005
Posts: 10,179
Likes: 2,306
From: Wesley Chapel, FL Las Vegas, NV
FYI, the Meziere WP for the LS family of engines flows a constant 55gpm as mentioned in the link below. The Evans mechanical pump addresses the high rpm cavitation issue with their own special mix designed specifically for their "system"
http://www.meziere.com/displaycatego...44,332,358,388
http://www.evanscooling.com/index2.html
http://www.meziere.com/displaycatego...44,332,358,388
http://www.evanscooling.com/index2.html
No problems at all in over 2 years. And not many places hotter then Vegas in the summer.
btw. I did loose the belt once and due to the EP I was still good to drive for awhile. Just no PS
Platinum Supporting Vendor
Joined: Sep 2001
Posts: 5,730
Likes: 270
From: VENTURA Ca
I'll pose a weird thought here. ( I am NOT an electrical engineer in any way)
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
I'll pose a weird thought here. ( I am NOT an electrical engineer in any way)
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
Safety Car
Joined: Nov 2002
Posts: 4,025
Likes: 2
From: Valdosta GA
I installed my Mez electric WP soon after installing my Supercharger. Its been working great for 3+ years with over 25K miles. The car is my daily driver still as well (most recent dyno is 633 rwhp). I installed a Dewitt's radiator about 1.5 to 2 years ago and this combination has been great with South Georgia heat. Only real problem was a blown fuse at one point but rewired it to a relay and haven't had any problems since.
Premium Supporting Vendor
Joined: Oct 2004
Posts: 23,599
Likes: 1,225
From: Providing the most proven supercharger kits for your C5/6/7 609-752-0321
I'll pose a weird thought here. ( I am NOT an electrical engineer in any way)
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
We did that on Asmokegars old Coupe a few years ago, it worked great. The car would get a little too hot after a good romping or 1/4 mile pass, not over heating, but hot. We put a BAP on the Meziere for giggles since there was one in the car that we were not using, and it helped keep the temps down on high RPM runs.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
I'll pose a weird thought here. ( I am NOT an electrical engineer in any way)
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
What if you ran a BAP to the water pump? Would it pump more water under boost?
I certainly see that on almost any car that if you hold the RPM at 1200-1500 RPM, the temp definately comes down. That tells me that we need more water flow at idle and low speeds. This is where the electric water pump helps.
Would the BAP help at high RPM?
Charlie: You're the electric motor guy. What say you on this?
We did that on Asmokegars old Coupe a few years ago, it worked great. The car would get a little too hot after a good romping or 1/4 mile pass, not over heating, but hot. We put a BAP on the Meziere for giggles since there was one in the car that we were not using, and it helped keep the temps down on high RPM runs.
I like that idea, I bet Nouman already has his order in 
Drifting
Joined: Jul 2004
Posts: 1,713
Likes: 2
I am beginning to start a big LSX (430) twin turbo (68's) build and I am trying to decide best way to cool the motor. I hoped this thread would help but it looks like there are two camps on this. Electric WP's are great and Evans (mechanical) pumps are great. My question...if you plan to run on the street not drag or road race and are worried about heat (twins create a huge amount of heat) is electric the best choice or stay mechanical? I know I may create lots of differing opinions but what I would like to hear is from tuners or folks who may
have used both. I can't judge when you only have experience with one type. Tuners would be the best help as they have multiple experience. My builder will do either but my tuner is not a huge fan of electric WP's. Thanks so much in advance!
have used both. I can't judge when you only have experience with one type. Tuners would be the best help as they have multiple experience. My builder will do either but my tuner is not a huge fan of electric WP's. Thanks so much in advance!