Electric fan & Water pump installation

[eventhorizon66]

I don't see how an electric water pump can increase fuel economy (unless you use solar panels on the roof to run the pump ).  Any load removed by eliminating the mechanical pump will be transferred to increased load at the alternator.  So all you've done is decrease reliabilty.  Does anyone (other than Horsepower TV as they are NOT a trustworthy sorce of info) have any evidence to the contrary?  The only reasons I can see one might want an electric water pump is to keep cool between runs (as Lorne said) and to keep cool at sustained idling/low rpm (cruising at car shows).

[Skunksmash]

If the electric motor is more efficient than the mechanical belt driven pump, then there is some energy to be saved there. However small it may be. All they did to the camaro on the show was the water pump, a fuel pressure regulator, a TBI spacer, flow through mufflers, and a better air filter intake setup. I think it was one of those K&N ones you can buy. So even if it only helps 1.003%, what's the harm in buying an electric as a replacement after the mechanical finally dies? At least then it would be more justifiable. And all those little percentages finally stack up to be a worthwhile percentage.

[eventhorizon66]

Without knowing any more than that, I'm sure all the mpg gains on that Camaro came from the exhaust and the intake (those things increase efficiency by reducing pumping losses).  Did they also perform a tune-up that some how wasn't credited for any additional mpg?  It is not just a matter of the electric motor being more efficient than the mechanical water pump.  Consider the whole system.  A mechanical pump is as simple as the pump, two pulleys, and a belt.  The electric pump includes an electric motor, a pump, wiring, and an alternator (which includes at least two pulleys and a belt).  My bet is the electric system will consume more power to pump the same gpm of coolant.  On this note, I'd say it is possible to increase efficiency by reducing the amount of coolant gpm to the absolute minimum required by the engine, but this practice would be risky for obvious reasons.

The "harm" in an electric pump is increased cost, reduced reliability, and increased complexity.  IMO, the gain is nothing for a daily driven street car.