looking at electric water pumps... there are the Craig Davies type which have 80 and 115 l/m capacity, then there is the bosche type which has about 10 l/min capacity.
The Craig Davies 80 l/min one says suitable for upto 3L engine and turbocharged engines.

Does anyone know what coolant flow rate our engines need ?
difficult i know with the std mech pump as it changes all the time with RPM...

What a cool idea!

The Datsun 1200 spec is 12 liter/minute @ 5 meters. Outlet is 1 inch inside diameter. It requires the maximum flow at peak HP, so it depends on how much HP you will build in, and the radiator size/efficiency.

For drag racing, you can turn off the pump while accelerating. For street use, an electric water pump decreases the reliability (because the standard mechanical pump is virtually 100% reliable).

I've got an 80lpm Davies Craig pump on my A15 with a pump controller. Most of the time it just pulses (when I can hear it). The controller replaces the thermostat for regulating coolant flow by adjusting pump speed based on a temperature sensor. Once up to temperature I don't see the needle move at all. Don't ever run the pump dry, they have ceramic seals in them that don't like to be run dry.

I've also got a electric fan switched off a 70°C thermo switch mounted on the radiator outlet. Comes on when it needs to.

schmick. Got any photos?

Don't reckon I do, next time it's all apart and visible I'll try remember to take some shots.

Hi Lamb-daiquiri,
Thats the same setup i am considering, i like it that the pump varies the flow to control the temperature and runs on after engine shutdown to reduce heat soak.

The controller can also operate electric fans as well...
I already have a water pump blanking plate that i bought from this forum a year or so ago....

No complaints on my setup, it's pretty oversize and I'm pretty confident it'll support anything I want to do in the future. When it's idling the pump just pulses, other times I can't hear it so I don't know. That said, my car doesn't get used much...

I just used a dump thermo switch for the fan because it can take the full fan load so it was just a matter of wiring it between the fan and ground. +ve comes off the ignition on line.