Tom Wilson
June 2, 2011
Photos By: Courtesy Of Edelbrock

Making room for the incoming air, the blower’s drive mechanism connects to the front of one rotor, which is in turn geared to the other rotor at the rear of the rotor pack. Careful blending of the intake air passage and the driveshaft ensure good airflow into the supercharger. Thanks to minor packaging differences between the Three-Valve 4.6 and Coyote 5.0 engines, the drive snout on the Coyote E-Force is similar, but not identical to the ’05-’10 Edelbrock Three-Valve E-Force kits.

The standard Coyote kit also retains the stock airbox and mass air meter, although a replacement air-inlet hose is used to accommodate the slightly displaced throttle body. Reusing the airbox and its built-in hydrocarbon trap avoids legal complications with the California Air Resources Board; a freer-breathing cold air intake is optional for off-road applications.

We’ve seen the E-Force/Coyote combination doesn’t need much boost, and consequently its need for charge cooling is minimal as well, but this kit essentially has the same good water-to-air charge cooler found on the company’s Three-Valve E-Force kits. It consists of a flat-element intercooler inside the supercharger assembly, plus the heat exchanger mounted just behind the front bumper and an electric water pump to circulate the coolant. A plastic header tank provides fill and venting points.

For daily runabout duty the intercooler is a nicety, but it comes into its own when having a long horsepower session on back roads and plays an important role in steadying the air-charge temperature during hot transients such as big decelerations followed by wide- open throttle. It’s also needed with the elevated boost pressures generated by a small blower pulley, which many of these Coyote kits will no doubt see.

It was only a few years ago that chronic belt problems—thrown, shredded, and slipping—were the constant background squeal in the Mustang supercharging world. Attention to engineering details has retired those issues says Rob, and in Edelbrock’s case collaborating with an original equipment belt-drive specialist engineering firm was key in developing a trouble-free drive. Extensive computer simulations of belt drive loads and dynamics were the main engineering thrust, with approximately 20 possible belt and pulley layouts thoroughly analyzed to arrive at a quiet, stable system.

Naturally Edelbrock took advantage of the notoriously unused-by-Ford bosses cast into the timing cover to mount a flat aluminum plate. The plate, in turn, provides mounting for a busy bunch of idler pulleys plus a seriously upgraded belt tensioner. (Rob characterized the stocker as “wimpy.”) The blower pulley thus gets a full wrap of the six-rib drive belt shared with the Coyote’s alternator and water pump. As with the Three-Valve E-Force, the shared blower belt has proven issue-free even at elevated boost levels.

We were able to drive Edelbrock’s automatic ’11 Mustang GT test mule. It drives just like the dyno sheets says it would, with a good hard hit right off the bottom, then tearing up the tach to the fuel shut off without a hitch. The automatic and blower make a great combination; just laying into the loud pedal is enough to haze the tires from a standing start, and with an abundance of torque on tap acceleration is your ready companion. Top end, we can assure you, is hardly in short supply, either. It was far more power than we were expecting from such low boost.

What is uncanny is how silent the E-Force Coyote combination is. In over 20 years of testing supercharged Mustangs we’ve endured the coffee grinding of the early centrifugals, heard belts and gears so loud they’d wake you up if you’d been dead but a week, noted how the move to helical gears was a huge step forward and we’ll admit just barely being able to hear some newer blowers. However, this is the first time we truly couldn’t hear anything. Oh, there’s the faintest boost whistle at full chat, but the rest of the time there’s nothing. No softly grrrring gears, no screams of ecstasy—just an otherworldly Coyote thrust.

Thankfully Edelbrock has been letting us sample their projects earlier in their development cycles, which means our test car was fully calibrated for power, but final driveability tweaks were still forthcoming. Still, the only anomaly was occasional light surging at low speed, part throttle that will be gone in production E-Force tuning. In other words, the E-forced Coyote has the manners of a showroom stock GT, but simply runs much harder. Given the refined nature of the newest Mustangs it’s a great upgrade.

Edelbrock is in a good spot with its Coyote blower. The performance is certainly there with surprisingly low boost. While there is an argument pitting the Eaton TVS against the Lysholm screw in heat efficiency, at the single-digit boost levels the Edelbrock-Coyote responds to so well on the street the argument is likely academic, but at 15 psi or more another technology might have the advantage.

What is a clear advantage for the Eaton TVS is less expensive manufacturing, which reflects in the Edelbrock Coyote kit’s “approximately $6,500 retail” price as quoted by Edelbrock. Now, pricing is always a minefield, and Edelbrock has many dealers, including the aggressive major mail-order houses, so actual sales prices could well be lower. Edelbrock noted the Coyote blower would likely be slightly less expensive than its Three-Valve because the Coyote deletes the Three-Valve’s cosmetic coil covers and unnecessary-with-the-Coyote-throttle body upgrade. Given the Coyote kit’s completeness, handsome finish, and Q9000-quality internals, that’s good speed for the money. 5.0

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