lets discuss electric water pump

[sweetlikechutny]

Well after changing the water pump on my winter beater mr2 (mid engine is pain in the ass), it occurred to me maybe it would be nice to have an electric water pump on my supra.
I have already removed the belt driven fan and installed an electric one. I will be ordering a adjustable temperature switch soon.
My idea is to have no more belt driven pump and only activate the electric pump along with the electric fans at a preset temp (180F?). Anyone see any problems with this?
I see some advantages: no more overheating while sitting in Toronto traffic (electric will always be full speed once activated), less drag on the belt system and quicker warm up of the vehicle because the coolant would not be circulating when the temperature is not reached.
What do you guys think? Has it been done before? And what pumps should I be looking at?

 

[shaeff]

the water pump should always be running. otherwise you'll overheat.

think about it- you have the e-pump hooked to a switch, your thermostat opens, and the coolant doesn't move anywhere because it's not getting pumped. the radiator will see very, very little hot coolant, and when there's no heat being transferred anywhere that it actually counts, (ie: radiator), you'll most definitely overheat.

 

[cuel]

I see some advantages: no more overheating while sitting in Toronto traffic (electric will always be full speed once activated), less drag on the belt system and quicker warm up of the vehicle because the coolant would not be circulating when the temperature is not reached.
What do you guys think?

If you're overheating in traffic, either the e-fan you're using is to small, the shroud is trashed, or you're running the a/c, and the condenser fan isn't working correctly. Does your fan even have a shroud? Does it cover the whole radiator? Did you leave the condenser fan(s) in place, or compensate by adding a smaller fan connected to the A/C switch? You'll need a bigger alternator, which is going to add drag every time the fans and pump kick on. Don't know if it will equal the stock water pump. Iirc, electric pumps don't flow as well as belt driven ones, either. As far as I know, they are only recommended for drag racing use.

 

[IJ.]

I run an electric waterpump as a booster.

Either pump will flow through the other depending on which is faster so it's not restrictive.

I have the MoTeC controlling it but Davies Craig do a full PWM controller.

 

[sweetlikechutny]

the water pump should always be running. otherwise you'll overheat.

think about it- you have the e-pump hooked to a switch, your thermostat opens, and the coolant doesn't move anywhere because it's not getting pumped. the radiator will see very, very little hot coolant, and when there's no heat being transferred anywhere that it actually counts, (ie: radiator), you'll most definitely overheat.

But thats why I would have the water pump switched to turn on when the thermostat opens.

 

[sweetlikechutny]

I run an electric waterpump as a booster.

Either pump will flow through the other depending on which is faster so it's not restrictive.

I have the MoTeC controlling it but Davies Craig do a full PWM controller.

I like it! What pump is that?

 

[sweetlikechutny]

If you're overheating in traffic, either the e-fan you're using is to small, the shroud is trashed, or you're running the a/c, and the condenser fan isn't working correctly. Does your fan even have a shroud? Does it cover the whole radiator? Did you leave the condenser fan(s) in place, or compensate by adding a smaller fan connected to the A/C switch? You'll need a bigger alternator, which is going to add drag every time the fans and pump kick on. Don't know if it will equal the stock water pump. Iirc, electric pumps don't flow as well as belt driven ones, either. As far as I know, they are only recommended for drag racing use.

I do admit that my efan that I am using in insufficient. I just thought this might be a nice idea.

 

[IJ.]

Davies Craig EWP110

 

[GrimJack]

The advantage of this is that you should be able to set it up to run the pump and fans after the engine shuts off, to keep coolant flowing until it cools down enough to close the thermostat anyway.

 

[IJ.]

Dave: I don't bother as the high mount turbo thermosyphons nicely once you shut the motor down.

 

[sweetlikechutny]

If I were to remove the belt driven pump altogether what kind of flow am I looking for in an electric pump

(I have upgraded the alternator already, additional 70 amps, so power draw is not too much of a concern)

 

[StevO9389]

electric water pump is a good idea but having it turn on when the thermostat opens is not. i ran a Meziere (sp?) that flows 43GPM on my LT-1 without a thermostat and ran all the time with the motor. the best part is you can leave it on with the car off to cool faster. the motor almost never got hot enough to turn the electric fans on which were set to 180-190. it came with a 2 year warranty and a 2500+ hour life expectancy.

 

[Supraholics]

What's the point of an electric water pump? Would it allow the motor some more static HP or easier revving?

 

[StevO9389]

What's the point of an electric water pump? Would it allow the motor some more static HP or easier revving?

it could alleviate some parasitic loss but nothing really signifigant. they usually outflow mechanical water pumps by a good margin and keep engine temps down a lot. you can leave it running with the car off so you can hot lap it. essentially they are made for racing applications but i have had absolutely no problem running one on the street as a DD. it is also one less bearing to sieze up on you however, they will burn up very quickly if run dry.

 

[Adjuster]

The meat of the problem as it's described here is not the pump pushing the coolant around, but the lack of airflow over the radiator due to the crappy E-Fan.

You can pump coolant till the cows come home, but if you can't get airflow over your radiator, it's a moot point.

Here is my reccomendation.
1) Get yourself a correct clutch fan that bolts to the water pump, and the stock shroud that goes around it.

2) Enjoy having a Supra that will no longer overheat in traffic with the AC on full blast.

3) If you want to improve your cooling system, buy a bigger "race" type radiator from Fluidyne, CSF, Toyo or whoever with more coolant capacity, and more fin/tube cross section area.

E-Fans suck. I have yet to see one that will flow as much as the stock fan with a good working clutch and shroud on it.

Simple? Yes. Easy? Yes to that too. (Most people just want to cut on losses, or this and that. They think the .4hp they pick up with the fan gone is really going to make a huge difference, but then bitch about the fact that the larger alternator needed to power it takes more power, or that they can't run the AC in traffic under 30mph... Blah blah..)

The undertray is important if your a speed demon, but in traffic, it's all about the fan and shroud system on any vehicle.

 

[Poodles]

Mechanical fan is MUCH more durable...

same with the waterpump...

 

[Supraholics]

So is untrue that you can pickup around 10hp by using e-fans? Plus e-fans allow the motor to turn easier, thus providing faster response??

 

[IJ.]

Think about where the power to turn the e-fans comes from?

 

[BGood]

I had a wrecked supra with an electric fan on it, so i took my clutch fan off and put this on, and I was amazingly surprised at the difference i noticed. think about this, 1 pound coming directly off of the crank is 2.7 horse, so lets say the fan weighs 5 pounds, which is an underestimate, thats almost fifteen horse. but dont forget, when that fan starts moving air it is probably the equivalent of about double the weight, if you catch my drift.

 

[IJ.]

Right up till the car cooks in summer traffic anneals the head and totally fucks itself......

Then you can tell people how you picked up maybe 5hp at most after you factor in the extra drag on the alternator to run the electric fan.. :nono: