I found a company called Davies Craig that sells one. I wonder if anyone has done this. In order to use a KZ for autocross I need to be able to idle for up to 5 minutes at a time. Do you simply replace the axle pump or add the electric one?
If I were to turn the electric pump off just before taking off, would the non-functioning pump block the water from being pumped by the axle pump?
Simply replace the axle pump. You could do both, but that would be silly and add weight and complexity that you don’t need. I would suggest running a thermostat so the engine doesn’t stay cold as the electric pump will likely run at 100% duty cycle without some sort of programmable controller.
You could. That assumes you know the temperature – a water pump that is turned off will not flow water past an in-line temp sensor, especially if that sensor that is further downstream. You could run the temp sensor directly off the engine’s outlet and have a better idea.
I think your application warrants a thermostat which opens the path for the radiator, but keeps a closed-loop (with the thermostat) when warming up.
I’ve used that pump for 10 years, and they work great. During warmup, I do regulate temperature by turning it on and off. I do use a modified IAME Leopard thermostat for those times I may not have adequate time for a proper warmup.
I think that is a great idea if you have to already add weight to the kart. I would imagine you would have to run a battery to power the EWP. I run the Davis Craig on my SCCA race car and love it. No need for a thermostat, the controller takes care of all that. I have mine controlled via the ECU and it’s speed is controlled by RPM and temperature. The DC controller basically does all the hard work and keeps the engine cool. I will have to do my homework on that since I have 35+ # of lead on the kart to make weight.