Hey everyone. I'm lookin' to possibly convert to an elec. water pump in my Z but I've got some questions. What does the OEM mechanical unit flow? What would be an elec. pump with a similar flow rating? Would I need a pump that flows just as much as high RPM as the mech. unit? Thanks in advance.

 

This is a highly debated issue, as the electric flows the same rate ALL the time, whereas the mech flow increases with RPM.
That being said, I have a CSR elec, and have had no problems with it.

 

I just bought the CSR, as some people have said the higher volume of the Mezeire HD pump doesn't allow the water to sit in the head long enough to absorb the heat. So, take it for what its worth, and make your call...

 

I've got the regular Meziere and wired it with the Painless wiring kit (definitely worth the $30) and its been great! Got 9-10 rwhp on a Mustang dyno and so far so good. The only thing I am getting used to is that the pump flows at a constant rate regardless of engine speed so it tends to run a little hotter at speed, BUT way cooler at idle, in traffic which is a plus.

--Alan

 

Thanks for the replies so far guys, I appreciate it. I was looking at going with the CSR (formerly CSI) pump from Summit and getting the Painless wiring kit Summit recommends. However, I read somewhere that the stock mechanical pump flows up to 45 GPM, whereas the CSR only flows up to 37 GPM. Is there any truth to the flow rate of the mechanical pump? If so, would this still cause it to run hotter like ABA is seeing? Thanks.

 

I am also looking to upgrade to an elect pump, nice thread. I was wondering does that painless wiring kit include a warning light or manual switch?

 

Jazsun, while I don't know the flow rates of the stock pump it flows more as rpms increase because its driven off of the motor (cam) which may account for the higher flow rate. The EWP is either on or its not and it runs at a constant speed regardless of rpm which is why I think it runs a tad warmer at cruise. BUT when your idling around in traffic, staging lanes, etc your EWP is still flowing at 37 gpm and runs way cooler, which is a big plus in my book. You also have to remember to bleed the system after you do the install...The Painless kit includes a relay, a circuit breaker and plenty of wire with really good instructions. Someone around here was selling/making a water pump watch dog set up with a buzzer and warning lights to alert you when the pump begins to draw more amps which catches a failure just before it happens...

--Alan

 

Thanks for the info. Maby I will just go that route cuz I suck at wiring.

 

Only if it's broken. The stock pump flows about 66 GPM at 6000 RPM. And that's pushing the coolant through the engine and the rest of the entire cooling system--not "free flow" which is how most electric pumps are rated.

Around 10 GPM at idle, depending upon idle speed, of course.

 

Wow . So, if I go with an elec. unit, I should pretty much expect it to run warmer while cruising unless I go with with Meziere HD unit, right?

 

Yeah, I've been bugging them to make us a pump. No luck yet.

Their LS1 racing pump flows 140 gpm.

 

The way electrics free up power is by not flowing as much, simple as that. The work of moving the water takes energy with a mechanical more rpms means more water flow and more energy is needed to move that extra water. The electrics flow a steady amount so they don't add extra load as rpms increase, they also flow LESS than what the mechanical would at higher engine speeds. If they flowed as much as the mechanical even a more efficient impeller would allow them to at best only be as parasitic as a mechanical because of the energy loss when it changes from me chanical to electric and back to mechanical energy so they should draw more energy, but a better impeller could make up fo some of that.

I am not saying electrics are all bad or anything, just thought I would add a little more science to the discussion.