5.0 Mustang & Super FordsHow To Engine
ATI's Stage I & Stage II ProCharger Kit - Stage Fright
ATI-Procharger's Two-Pronged Approach To Frightening '03-'04 Cobra Performance
Though we knew our little Real Street class might become a testbed for racing technology to transfer to the street market, we didn't know it would be quite this direct. The P-1SC2 supercharger raced by the likes of Justin Burcham and Tim Matherly is the same self-contained blower packaged in ATI's Stage I '03-'04 Cobra kit. Better yet, it's good for 600-plus-horsepower at the wheels in a completely streetable car.
Modified '03 and '04 Cobras are the rage. Add a chip, a pulley, a cold-air kit, and an exhaust, and these cars will make power we had only dreamed of from such mild modifications. The bottom line is, Ford really outdid itself with these cars. They are hot rods right from the factory, and they're ripe for the modding in the hands of power-hungry enthusiasts. If you're tired of reading about them, it's probably because-like us-you don't own one. And, you think it's all been written by now, so we should be on to the next thing.
Well, the next thing-the '05 Mustang-isn't here yet, and by the looks of what we've seen from ATI-ProCharger, we haven't read the last story about big-power Cobras. But wait a minute. These Cobras already have superchargers, and the really power-crazed are replacing them with screw blowers. So, why are we writing about ATI? If you checked out our SEMA coverage in the April issue ("Truckload Scale," p. 82), you no doubt saw that ATI had debuted its centrifugal conversion kit for '03-'04 Cobras. We'd heard of it before then, and we've been chasing the story for months. So determined were we, that we convinced ATI to let us inside some of its testing on the Stage I kits as well as on a sneak preview of the insane Stage II kit-but more on that later.
When we first heard the Cobras were to have factory superchargers, we assumed it would take a bite out of the companies that do brisk centrifugal business turning '96-'01 Cobras into blown terrors. So why would ATI-ProCharger create a centrifugal conversion kit for a car with a Roots-style blower? It's fairly simple, really. ATI's Dan Jones says the main reason is the car's purpose-built blower motor. Installing a supercharger on an engine built for one is a far more attractive proposition than making one work on a naturally aspirated engine with high compression and light-duty pistons. Additionally, the company saw it as a way to allow the market to directly compare its self-contained centrifugal blowers with the likewise self-contained Roots-style and screw blowers. And it certainly didn't hurt that customers were asking to buy such kits.
Though ATI had kits that would bolt to the Four-Valve 4.6 from its '99-'01 Cobra and Mach 1 kits, the real challenge was adapting an upper intake to replace the factory Roots-style blower, as ATI wanted to take advantage of the factory air-to-water intercooler. Beginning in the summer of 2003, several prototype intakes were built, with the main challenge to achieve adequate airflow while making the part relatively easy to manufacture. Along the way, ATI consulted with Ford engineers to learn just what these engines like, which apparently is plenty of boost-as long as you keep the rpm under 6,500 or so when the cams run out.
Along with determining how to install the blower on the car, it was important to choose the right head unit for the kit. ATI is never shy about creating a blower for a specific application, but after doing some blower mapping, the company determined that its P-1SC2 blower-spec'd for the Real Street class-fit the bill, as it is a potent torque producer, which follows along with the intent of these cars.