Though the basic short-block is the familiar 4.6L engine inside an aluminum 4.6 block, the engine is new and improved, with the top half receiving a significant performance makeover. First and foremost are the Three-Valve cylinder heads, but the intake manifold and computer-controlled variable cam timing are new to the Mustang as well. All told, this engine produces more power than a Two-Valve, but it does peak a bit higher (see "Testing Two, Three," p. 58). The thing is, it doesn't really translate to the driving experience. Perceived power comes off a lot like the '03-'04 Mach 1, in that it's a balanced car with decent power, but it could really use a blower. In fact, these cars weigh nearly as much as '03-'04 Cobras, but those cars have 390 hp and brutish bottom-end torque. The '05 doesn't.
Those Cobras also don't have an all-powerful computer in the kick panel. Replacing the familiar EEC V processor on the earlier 4.6 Mustangs is a new, more powerful processor dubbed Spanish Oak. This faster computer obviously allows controlling more operations such as electronic throttle actuation and variable cam timing, and more precise control of everything under its sway. According to Ford, Spanish Oak's 40-MHz Motorola MPC-565 processor packs eight times more computational power than the 27-MHz processor in the EEC V. As such, Spanish Oak can handle electronic throttle, variable cam timing, and automatic transmission controls while still having 15 percent of its capabilities in reserve. The EEC V couldn't do all that at maximum capacity.
In addition to enabling the high-tech throttle control and variable cam timing, the new processor also enables what Dr. Meyer dubbed "adult supervision" (see First Blast sidebar). We had heard the new cars deliver torque on demand, but what Spanish Oak giveth, it can, apparently, take away. In my experience, that means the computer seems to close the throttle blade before the driver is in danger of causing a warranty claim. Officially, Ford says the car has no such feature, but suffice it to say it felt as if the engine was dying during burnouts despite trying to hold the rpm at 5,000-and I had the traction control off, as burnouts are impossible with it on. This overbearing application of processing power is a real downer, but at least it will be a boon to electronic tuners, who will sell flash tuning by the boatload if they can circumvent this phantom feature.
Yet, I can't condemn the car for not being fast enough or the computer for being too conservative. I've yet to meet a stock Mustang that was fast enough for hard-core Mustangers. Fortunately, that's what makes Mustangs so interesting-taking a great car and modifying it into a better car that's all your own. The good news is, despite the obvious investment in reengineering the Mustang, its cost of entry is still shockingly low. While a solid axle, four seats, a performance intent, and sporty styling are all part of the Mustang spirit, the fact that you can score a base GT for $24,995, and a Premium GT with standard Shaker 500 audio and leather seats for only $26,330 means your neighbor with the '04 Mustang is really gonna be jealous, and that the Mustang as an affordable sports car is still alive.
Half-Dozen CousinAs cool as the '05 GT is, it's the base V-6 model that may steal the show. This sub-$20,000 car gets the great new chassis, most of the improved suspension, and more horsepower than a '93 5.0. That's right, the new-to-the-Mustang Two-Valve, SOHC 4.0L V-6 in the '05 Mustang produces 210 hp at the flywheel-5 more than the beloved pushrod 5.0 in the Fox car's swan-song year. Yes, the '05 weighs more, and it makes notably less torque than the old 5.0 (240 lb-ft versus 275 lb-ft), but it's hard to overlook the potential of an overhead-cam 4.0 with a 65mm throttle body, forged connecting rods, multilayer-steel head gaskets, and only 36 ci less than its V-8 cousin.