Mark Houlahan
Brand Manager, Mustang Monthly
May 1, 2005
The Meziere 5.0 water pump flows 55 gallons per minute and will surely keep your hot 5.0 engine cool. Available in several anodized colors, as well as polished aluminum, the pump sells for around $460, racer net pricing. The pump is rebuildable, and Meziere tells us that for street use we could expect about 50,000-60,000 miles of service before requiring a rebuild. The rebuilding process-and only the motor assembly needs to be removed for rebuilding by Meziere-will run about $120, where the pump motor receives new brushes, seals, bearings, and more.

Horse Sense: In the past, running an electric water pump meant either rigging an electric motor to turn your stock belt-driven pump or using a race-oriented electric pump-either way you lose your serpentine-belt setup. The electric pump's motor on these race designs wasn't meant for continuous street use. The pump body wouldn't clear all the brackets and such in a street application either.

Last month, when we dressed Editor Turner's new Probe Racing Components 331 stroker for street duty ("The One," Apr. '02, p. 133), we briefly mentioned installing the new Meziere Enterprises 5.0 electric water pump. Unfortunately, we didn't have room to show anything more than a product shot at the time, but we kept the camera rolling and caught the install and wiring on film-albeit digital film-for you. The installation is a typical small-block Ford water-pump replacement and is textbook in nature except for having to wire the electric-motor circuitry.

Our only snafu came from the previously installed Paxton Novi 2000 supercharger bracket. The bracket's beefy stance gets in the way of the right-most water-pump attaching bolt, necessitating the loosening-and practically the complete dismantling-of the blower bracket. A grinder probably would have made the clearance we needed, but it wouldn't have looked pretty. Note to Paxton engineers: Machine some clearance for the water-pump bolt, because a Ford wouldn't be a Ford without having to replace the water pump at least once in the engine's lifetime.

So why use an electric water pump anyway? For one thing, it reduces the horsepower loss from having a belt-driven pump on the front of your engine. It's one less thing to drag down the crankshaft's power. If you're running sans A/C and power steering, the water pump is the last vestige of horsepower loss on the front of your 5.0 (not including your alternator, which you must have).

If you've never replaced a factory belt-driven pump before, the removal is covered in many shop manuals. In a nutshell: Remove the fan, the pulley, and the A/C support bracket, drain the coolant, and remove the hoses. Then remove the pump mounting bolts.

We know what you're thinking. If you run an electric water pump, it will increase your alternator draw and make the horsepower savings a moot point. But this is not true. The Meziere pump draws only about 10 amps-not enough to make the alternator load affect horsepower. And, with an electric water pump, you can wire in a manual override switch to run the electric pump with the car off. Do the same for your electric fan, and you can circulate coolant and cool it between rounds at the track. Not a bad idea, eh?

This all sounds warm and fuzzy to us 5.0 fans, until you actually try to install one of the previously available electric water pumps. Guess what? Either the pump is designed for an older V-belt configuration or it's designed for racing applications where the alternator is the only accessory driven by a belt (usually a small cog belt). If you had a race car and it wasn't running A/C, power steering, and the OE serpentine belt, you could mount your electric water pump and save some horsepower.

For the rest of us street/strip enthusiasts who wanted to keep the serpentine setup (what if you had a blower-how would you drive it?) and A/C, we were out of luck.

What Meziere has done for serious street 5.0 owners is give us our cake with an extra helping of icing on top by installing an idler pulley in heavy-duty bearings on the front of the electric pump housing. The benefits of an electric water pump on a street car with A/C and full serpentine belt routing? Where do we sign up?