91redz28

i am looking to put an electric water pump on my GTA. what are the pros and cons of an electric water pump.

c-u-later

go with a mechanical pump. i have a 550hp 355 in my 84z and a large alumminum radiator and i have ran a moroso electric and a proform electric and it always ran about 180 to 210 and my engine builder said that was to hot and recomended a stewart warner EMP mechanical pump now it runs 160 to 170 on a 95 degree day! ihave also used a becool fan setup for couple years now.

91redz28

how much did the pum you are using now run you?

Gramps

iTrader: (1)

i dont believe you tried all the moroso or proform models my friend. maybe you had an average pump, perhaps you shoulda upgraded to something that flows more. my CSR will flow enough to supply a big block, and its for a sb. mechanical pumps dont look cool either (my opinion).
another great feature is its rapid cooling abality. you can idle and still have full flow, and when your engine overheats at the track...just turn off your motor, turn on the pump and let'er cool down.

on the flipside, do you wanna spend extra money for an alternator and p/s pump bracket kit, because electric water pumps dont have all the extra holes and stuff that a stock mech pump does. unless you buy one of those mechanical conversion pumps where all you do is remove the front assembly and replace it with an electric motor as opposed to the pulley and belt system.

ryan91rs

iTrader: (1)

they free up some power but i'm not willing to get a new serpentine system to get that power. maybe if i had a v-belt i could justify it. Plus a decent pump is only like $50 and under $120 for alumn.

still might get one someday but better things to spend that cash on for now.

Orr89RocZ

iTrader: (20)

i want to go to a electric pump just because it looks good and gives you better cooling options as stated above.
i think they can be lighter but thats not a big difference. I just dotn like the idea of getting more brackets and stuff to make it work

QuickStyle

electric could go out on you and overheat the engine quickly, at least with a mechanical pump when it goes out it still works, just leaks a little.

5678TA

if you use a electric, you need a special setup for your accessories.. that means good luck having a/c, alternator and p/s at the same time.. you also NEED good fans.. i have an electric and almost 5000cfm worth of fans(3 cooling fans total) on my car.. it keeps my 385 at a cool 170* on any day going uphill.. i would say dont go electric unless you absolutely need it.. a high-flow mech. unit will work fine..

91redz28

thank you, i am probably going to stay with mechanical. any suggestions on what company and model???????

QuickStyle

i hear good things about stewart, i got one, but not too much experiece with it yet. i got the aluminum stage 2 i believe it is.

c-u-later

I had a moroso and a proform and they just didnt work for my combo like the stewart EMP pump did.Thats all im saying!

scooter

iTrader: (11)

Not necessarily. The shaft can break and pull out the front of the pump, I think one of mine siezed once and threw the belt. Hard getting home with dim headlights

slim64

iTrader: (2)

I actually asked my engine builder this same question last week, and he was highly against electric pumps. His recommendation was to get a stewart.

This is why. An electric pump will flow with same at idle and high rpm but with very little pressure. This is because the flow doesnt increase with rpm. With a mechanical pump, flow increases with rpm, and the pressure increases with it.

You need pressure in the system to raise the boiling point of water. That is why they have anywhere from 13 to 17 psi radiator caps. Since the increased pressure raises the boiling point to about 260, it stops detonation and thus loss of power at higher rpm (when the engine creates the most heat)

Without this pressure waters boiling point will stay right around 212 and will cause steam, and hot spots to form, which increases your chances of detonation. Ultimately resulting in loss of power.

Once a cooling system has reached its boiling point, and has started to vent, it will NOT stop venting until the motor has been shut off and the coolant is allowed to cool.
(this is because of pressure raising the boiling point)

He was able to dyno test many high end electric pumps and also tested high end mechanical pumps, and the mechanical pumps won hands down, since they were able to control detonation better. The amount of power a mechanical pump *absorbs* was negated by the fact that the gains over the electric pumps at the top end were more than what it *absorbed*

Hope this helps, sorry if its hard to read, im sure someone can explain the science of it better than i.

-richard

scooter

iTrader: (11)

Cooling system pressure has to do with temperature and the radiator cap, not flow. Technically water pumps are not really pumps at all, they are water circulators. There is just a vane in there like a household fan (not exactly the same) and all it does is make a high and low pressure zone on either side of the vane. A PUMP would be a screw type or piston style and those can creat pressure, ie, an engine is a large air pump

scorchmaster

iTrader: (6)

Electric water pumps solved all my overheating problems. I have one for sale too, go nuts.
http://cgi.ebay.com/ebaymotors/ws/eB...178562860&rd=1

91redz28

welll i finally decided to go with a mechanical ( stewart). solved my problem my temp stays at 170 and doesnt move. thank you to all that have replied

joeblue83

iTrader: (8)

If you drag a lot or do a lot of city driving the electrical pump will out perform the mechanical any day. But there is a little higher chance of it going out. You will also gain around 10-15 horse by removing the mechanical one. I have a electrical pump and keeps my stroker at 190 on even the hottest days of the summer

StreetRoc85 350

[QUOTE=slim64;3525117

This is why. An electric pump will flow with same at idle and high rpm but with very little pressure. This is because the flow doesnt increase with rpm. With a mechanical pump, flow increases with rpm, and the pressure increases with it.

-richard[/QUOTE]


Coolant is a liquid and thus is NOT compressable. Scooter is right, water pumps are actually water circulators. Their job is to move coolant from the engine to the radiator and back again, not to pressurize the system. Pressure in the system is the result of having a heated substance in a sealed space. An electric pump can circulate water just as well as a mechanical pump provided that they have the same flow rates. The only difference is that there is an electric motor instead of a pulley.

Electric pumps will free up HP because they dont induce more drag as the RPM increases. They also will cool better at idle because they flow the same rate throughout the entire rpm range. So which is better? Well technically electric pumps are better because they free up HP and do the same job as a mech pump. Mech pumps are cheaper, more reliable, and probably last longer as well as the fact that they allow you to retain your stock belt setup. I havent yet decided which i will go with yet...

ryan91rs

iTrader: (1)

the pressure gets higher, that makes the surface tension of the water to go down and the boiling point to go up. I think it's a combo of the pump, heat and the cap. pump moves it, the water gets hot and tries to expand but the cap keeps in in the closed system raising the pressure.

WickedBowtie

Not accurate at all.

QwkTrip

iTrader: (22)

I can see how an electric pump would be more reliable. Just have to spend a decent amount on a good product.

I think it is the case that mechanical pumps have far greater flow than needed at high speed [RPM] because the pump has to be sized to effectively cool the engine at low speed. Don't quote me on this, but I wonder if that greatly increases chance of cavitation?