Don Roy
March 1, 2007
Photos By: Tracy Stocker

The technology, as mentioned, is scalable, so it can be made larger ... or more interestingly, smaller. As it happens, there is a mechanical module sitting on the front of this Mustang's Rotrex supercharger and what is inside has been derived from Mr. Antonov's insights. A small planetary gearset is used to provide a 2-speed transmission, so that the supercharger can be driven faster at low engine speeds. When dealing with centrifugal superchargers, boost is developed in proportion to the engine rpm - slowly in the lower range, but quickly (exponentially) in the upper range. Being able to overdrive the supercharger at low speeds means that the car will be much more responsive in normal, day-to-day driving and that's really where most Mustangs spend the bulk of their time.

Shift Happens
Of course, nobody wants to worry about when the box is going to change speeds, nor would it be helpful to have some complex hydraulic or electronic control system hanging off the side. Inside this mechanical module, more than a little clever design provides a gearbox that shifts based both on speed and load. This is important, because when you've got your foot in it, you'd rather keep the boost building right up to the maximum allowable. Sensing rpm is easy enough using centrifugal forces, but detecting load - mechanically - requires a little more ingenuity.

The key component in making this happen is called a 'helical' gear. It is so-called because the teeth on the gear run at an angle to the gear's body, making them look like a portion of a helix. Most often used in right-angle drive gearboxes, they can also be applied to parallel drive configurations. However, their most relevant property for our current interest is that they generate a thrust along the shaft that is proportional to the torque being transmitted.

Clever use of these two forces allows the speed of the supercharger, and thereby its output, to be adjusted according to the driving conditions. When you look at the power and torque curves, you'll see a step in the curves where the module has changed gears. Compare this to the curves for the Rotrex supercharger only and you should immediately see the benefits. In practice, the Antonov module shaves a full second off the car's quarter mile time and adds about 10 mph to the trap speed.

Demonstrating a unique concept like this also requires a reliable platform on which to build and the bottom end of this Pony's engine is where the folks at Wheel to Wheel started. The original rotating assembly was replaced with a forged 4340 alloy steed crankshaft, forged steel connecting rods and forged aluminum pistons. The stock aluminum block and cylinder heads were kept, along with the cams and valve train. Of course, a new intake system was called for and the fabricators at Wheel to Wheel began that task after the drive mechanicals and brackets were worked out.

Hunkering Down
The transmission and rear axle were left alone, however the suspension and brakes got an extreme makeover courtesy of Ford Racing and Baer. The Ford Racing FR-3 Handling Pack provided replacement struts and shock absorbers, lowering springs, front and rear sway bars and a strut tower brace. With these components designed to work together as a package, the car was dropped by an inch and a half for a more aggressive stance. Valving for the struts and shock absorbers was developed by Multimatic Motorsports - the company that built and tuned the 2005 Grand Am series-winning FR500C Mustangs. Gripping tightly on those suspension pieces are some top drawer anchor parts from Baer. The Baer Claw GT-PLUS front brake installation provides large 2-piston PBR pin-driven calipers and 14-inch, two-piece brake rotors. These disks incorporate an aluminum hat to reduce overall weight and allow for differential expansion of the rotor plates. Out back, the brake rotors have been upgraded to Baer's Eradispeed Plus 2 slotted and drilled models.