Inliners International Forums General Discussion Hi Performance all-electronic cooling system

i did a foolish thing, that has worked out pretty well... after a spate of cooling system problems i ended up making a fully electronic cooling system -- electric pump from Davies Craig via Pegasus Racing, wrote a ton of software for it, and now have a killer cooling system that regulates within a degree or two of setpoint. draws about 200 watts at full blast. been running this for most of a year. new engine, and i've added a separate and additional head/block circulation pump that ensures even heat and measurement separate from the radiator pump. software does full feature warmup, cooldown cycle, etc.

i can't find even one example of such a thing out there. the only use for electric pumps seems to be drag racing, where it's on/off, or crude control. mine's got two P.I.D. software control loops that holds temp tight as you desire.

ran it on a rally, here was the peak test: 26 of august, in Badwater CA in Death Valley, 112F ambient, climbing the 8% grade at full output 60 MPH, temp locked at setpoint 188F at what i estimate 80% capacity. $139 two-row Jegs aluminum radiator. probably 150 hp working hard.

hardware is arduino based, with some fat MOSFETs and two Stewart Warner sensors. controls coolant pump, radiator fan, and (new) circulation pump. half thinking of contacting Davies Craig to see if they want it. anyone interested in messing with this?

I believe that many hybrid electric cars use a similar approach as the gasoline engine is turned on and off - so the electric pump is needed to keep coolant flowing. But to your point it may be a crude on/off affair - not the sophisticated temperature set-point approach you've taken. I think that Audi, VW and BMW have used electric recirculating pumps in some models (in addition to the mechanical pump).

The options over at Davies Craig seem quite numerous.

Thanks for sharing.

Full electric cars have a very smart cooling system strictly for the batteries you ride on but still very sophisticated

Tom, What would a system like yours sell for?
It sounds like have it well thought out.

I've been running a Craig-Davies pump for three years in my Firebird and it works reasonably well. It's a tiny pump so I occasionally exceed its cooling ability when it's over 90ºF and I am driving over 75mph but I've never overheated, it's funny the coolant temperature just moves in direct relation to my driving speed at that point. Faster=hotter, slower=cooler. Once I get the turbo on my engine I plan on going to a much larger 55gpm Meziere pump. I also got creative with the cooling system and reverse flowed the cooling system so the head get's the cold water first to try and help stave off detonation (down the road).

Mine is current set up crudely as on at 185ºF and off at 180ºF, or if the engine is off, or if engine load exceeds a certain amount to get the coolant flowing when the load hits rather than as a reaction to the temperature. It does reasonably well at temperature control. I bought a Jeep solid state fan relay and plan on wiring it up with PWM speed control through the megasquirt, just haven't done it yet but will be more critical with a larger pump.

I couldn't get the controller to keep a tight temperature range, so I handed control over to the megasquirt.


The pump is located at the same level as the radiator outlet, runs up and tee's out with two 1" hoses going to the head where there used to just be freeze plugs. I put a plate over where the water pump used to be and bolted a thermostat housing to it, sans thermostat, and ran a hose from there to the radiator inlet. I purge the air out of the cooling system at the original thermostat location.



You can see the indicator on the bottom left showing the "Water Pump" is on. This was driving to Las Vegas in October, it was around 95ºF out.