46 replies to this topic

[ginigwunkle]

you sure its not a mechanical pump with just the fan removed, that alone adds aprox 4hp,

[*DJH*]

that is the mecahnical pump, the tech regs state that in my last two posts

[Dan1991]

How can you get away running no thermostat if you have a electric pump?

[Wessie28]

How can you get away running no thermostat if you have a electric pump?

i believe you can pre set all of the running temperatures, pumping flow etc and possbily some pumps may have a built in thermostat

Edited by Wessie28, 24 January 2008 - 09:40 PM.

[Jammy]

I'll be interested in this! I'm pretty much forced to using an electric water pump because of my subframe.

DJH, it seems you've posted the same regs twice?

[Dan]

The pump is not simply on or off, its speed is controlled by an electronic unit connected to a digital sensor. When the engine is cold the pump is barely running, as it heats up the speed of the pump is gradually increased. So long as the radiator is capable of cooling the water faster than the engine can heat it there will always be a supply of cold water. The pump just adds the same amount of cold water as the engine is heating up. If it tries to overheat, the hotter the engine gets the faster the pump runs so it is always pushing more and more cold water into the engine. The mechanical thermostat is only there to allow the engine to get to a certain temperature, the electronic system does the same thing by simply not running the pump if the engine doesn't need cooling.

[*DJH*]

DJH, it seems you've posted the same regs twice?

no they're similar regs, the first one was for mini7 and the second was for miglia.

[Wessie28]

The pump is not simply on or off, its speed is controlled by an electronic unit connected to a digital sensor. When the engine is cold the pump is barely running, as it heats up the speed of the pump is gradually increased. So long as the radiator is capable of cooling the water faster than the engine can heat it there will always be a supply of cold water. The pump just adds the same amount of cold water as the engine is heating up. If it tries to overheat, the hotter the engine gets the faster the pump runs so it is always pushing more and more cold water into the engine. The mechanical thermostat is only there to allow the engine to get to a certain temperature, the electronic system does the same thing by simply not running the pump if the engine doesn't need cooling.

you know your stuff ! wherea a mechanical pump runs constantly, but obviously gets faster as the RPM increases

[ginigwunkle]

so in theory the leccy pump will heat up faster?

[Avalanche325]

Taking the fan off and going to an electric one will give you a little more HP. It is also a lot easier that going to an electric pump and better HP for your money. Another plus is less load on the water pump bearings.

And you can still run a mechanical pump to meet the regs.

[Jammy]

Plus, the mechanical fan only aids cooling above about 15mph, after that it can actually restrict the airflow through the radiator, so technically you only need to be powering the fan below about 20mph (temperature dependant)...

I think....

[Timinichelsea]

Ok allow me to try and clear a few things up here.

Mini 7 and Miglias - none of them use standard mechanical pumps.

The car pictured belongs to Phil Rudge and has a standard water pump outlet without a pump - the electric pump can plainly be seen. that is a very old school set up and is very cluttered.

The regulations you posted are very odd i think they must refer to the S class which is entirely different. Electric pumps are not used for their HP advantages they are used for their simplicity and cooling benefits and the fact thay you can leave them on to cool the engine after the race has finished. I mean seriously rev limited to 8K! no way they regularly pull 9K in fact one of ours the other year pulled 11K.

As sprocket has said thermostats are not used.

And yes i do know what i'm talking about - i built the best prepared mini 7 2007 and help run a race team.

[The Matt]

Thanks for clearing that up

[Rosslin Racing]

I use a electric water pump on my race engine, I closed all the waterways between head and block and came out of the end of the block to take the water to the head. I also use a golf 2 rad up front and the pump with out control unit on it. A switch so i can let it run on for 10mins. it works great, at dijon midsummer you have around 35 degrees outside but the water temp is always around 80 degrees. for a road car I would not fit one after all your not racing.

[Dan]

Removing the mechanical fan from a conventionally cooled Mini is not a good idea. It is capable of shifting far more air more efficiently than an electric fan can, the air isn't going to travel through the rad on its own when the car isn't moving. Even when it is moving the airflow needs assistance. An electric fan replacing the mechanical one would have to be running continuously while the car is travelling slowly and they simply aren't designed for that. A Mini limping through traffic with no mechanical fan is pretty much guaranteed to overheat.