There's plenty more custom stuff in the R. How about a Bassani X-pipe and Borla mufflers with side exits? Ford also wrote checks to B&M for the Ripper shifter, to McLeod for an aluminum flywheel, to Bilstein for shocks, to Eibach for 800-lb/in front and 750-lb/in rear springs, to Fuel Safe for a fuel cell-yes, a fuel cell-and to Mobil 1 for oil. Naturally, the 18x9.5-inch wheels are unique-although these get copied faster than a calculus final-and the all-important tires were custom-tuned BFGoodrich super stickies. More than just a stripper Mustang with a big engine, the '00 R was the factory's big shot at putting the Mustang into the big time on a road course.
After reciting that winter-long list of special gear in the Cobra R, we should say the two engines we're dealing with here are the heart of the matter. For as vital as the differences in chassis specification and creature comforts are, the engines are what give these two powerhouses the most distinctive aspects of their personalities.
The '03 Cobra has the 390hp blown 4.6. Its beltdriven, Eaton-manufactured, Roots supercharger and intercooler assembly takes a hint of rpm to get running, then opens a floodgate of torque that ramps up through the mid-range and provides a bellowing top-end charge. Revving the blown Cobra is something of a big-block sensation. That's because it is so gung ho in the low- and midrange, and while revving lustily all the way to its 6,500-rpm redline, it doesn't signal any eagerness to exceed that speed. Well muffled, the signature noise from the '03 Cobra is a muted yet still exciting blower whine. The rest of the aural sensation is sort of a strong industrial presence of high-speed iron and heavily coerced air. Like a steel mill heard from across the street, the latest Cobra engine at full throttle has a real presence.
Pedaling the 385hp '00 Cobra R through a couple of octaves is a different tune. First of all, the side-exit exhaust is loud and clear-with that uniquely two-tone voice sidepipes give. And it's a crisp rip of an exhaust because the R's 5.4 makes power the old-fashioned way, with a happy combination of displacement, free-breathing cylinder heads, aggressive cams, a tuned intake manifold, and 9.6:1 compression. Unlike the whistling oomph of the blown 4.6, the '00 sounds like a Trans Am car letting loose in your living room.
The R engine also seems to pull harder. Some of it is a lack of torque right at the bottom. The larger but naturally aspirated R engine can't match the '03's boosted output at the slumbering end of the tach, so it necessarily feels as though it pulls harder once it gets running. And, sometimes all that torque combined with street tires turns more into wheelspin than thrust. The R could be more energetic at the rpm typically seen when running hard.
The point is, the power ratings are practically identical, yet the blown Cobra makes more torque, especially at lower rpm. It's even ahead in horsepower, and yet at the dragstrip, that didn't get the '03 to the finish line first.
If you're looking for where the '03 Cobra shines, go no farther than the nearest freeway on-ramp. A superb high-speed cruiser, the '03 has the gearing and muscle to effortlessly notch up the interstate miles, while simultaneously the truly plush ride, quiet cabin, and full suite of creature comforts makes it a relaxing experience. Cruising speeds can be whatever you want, with wind noise and fuel consumption not terribly out of line when pushing beyond today's highway speeds. It's also important to emphasize the '03's fine Mach 460 six-disc sound system and meat-locker air conditioning.
Get off the freeway and the Cobra shows its wideband power-curve agility. Hit hard and revved, the blower Cobra kicks out the jams in short order-no worries there. Make no mistake, this car is fast, even visibly fast to bystanders at the strip. When people remark how hard a car runs just from watching it, it's doing the deed.