Electric vs mechanical water pump (SBC)

[TLC76]

Either my search skills really suck or no one really talks about this much, but anyone here have real world experience with the mechanical vs electric water pump on a rock crawler/trail rig? Looked over on Pirate as well. I have read all the generic stuff online about how great it is for drag cars etc, but it seems that on paper at least when scrawling around at lower RPM's the constant flow would make sense. Of course going electric would be at least $300 with PS and alternator brackets, where a high flow mech pump would be about $100.

I also like the option of keeping the cooling system operating when you shut down for 2-3 minutes instead of heat soaking.

What says the think tank?

 

[Elbert]

I think for an off-road rig you are better suited to stay with the old school mechanically driven water pump. I don't see much advantage if any to an electric water pump. I would rather have the simplicity of the old school mechanical water pump...of which I could buy or obtain a spare about any where if needed.

 

[DC EWP]

I recommend you check out the Davies Craig line of EWP - Electric Water Pumps the cool thing about them is you can use them as a booster pump to the mechanical pump if you want to leave the stock unit in place. The best way is you modify your stock pump by removing the impeller and you also remove the thermostat and use their Digital Controller as an electronic thermostat. The result is much more consistent engine temps and improved cooling at low RPM since you are not dependent on engine RPM for coolant flow.

Check out http://www.daviescraig.com.au/

 

[TLC76]

Interesting, their flow claims are a bit less than the 35-55 I see from most mfg, the one I looked at claimed 115L a minute, which should be around 29ish GPM. I ended up going with a basic high flow mechanical unit, also found out my CSR temp gauge/fan controller is way off. at 110 deg it matches my ECU temp exactly, at 200 it reads 220 and so on. So I wasn't overheating as bad as i thought. ordered a good old mechanical water temp gauge.

 

[DC EWP]

The EWP115 is about 30 GPM and good for smaller V-8's or up to about 400hp. The EWP150 is rated to 800hp. Testing has shown the balance between too fast and good flow. The EWP115 is always an option as a booster to your mechanical pump. It will help with low RPM flow and eliminate cavitation issues during high RPM.

Where is your temp sensor mounted? The two most common issues are mounting in the head which is going to read hotter that the rest of the motor or when mounting in the intake you get a bubble or steam pocket at the sensor. This is an easy fix by just bleading the sensor. I've made this mistake before. If you have an inferred temp gun check both at the thermostat housing and where the top hose attaches to your radiator. This will give you and accurate temp of your engine to compare to your gauge reading. It's also good to check the lower hose on yor radiator to see how efficient you radiator is.