Two-Valve and Four-Valve are common Mustang terms and provide a clear definition between regular and premium 'Stangs. But get ready to add Three-Valves to the mix. When the '05 Mustang arrives, the GT will sport a 300hp Three-Valve modular engine, similar to what's under the hood of the '04 F-150 pickup.The Mach 1 was the fastest of the three to launchThe overachiever of the bunch is clearly the BullittWho'd have thought a Cobra was slower than a Bullitt?The Mach pulled the Bullitt by at least a car length, and that was that
Since our first spin of the tires, we've been saying the new Mach 1 is a special sort of Mustang, and on performance alone, it is. But considered in a wider view, the Mach 1, with its unique combination of naturally aspirated Four-Valve modular V-8 and live rear axle, represents a maturation of the modular engine. Once strictly the special treat of the SVT elite, the Four-Valve V-8 in the Mach 1 has moved mainstream, into the thick of enthu-siast action. Clearly when considering the modular engine family and the modern Mustangs it powers, we now have quite a choice in power, chassis specification, and vehicle intent-enough so it's high time to sort out the players.
So here we are sorting the Mach 1 with the still-new but already-out-of-production Two-Valve Bullitt, and a representative of the naturally aspirated Four-Valve SVT Cobra crowd. In our case, it was a '99 Cobra-more importantly, it was not the current '03 Cobra with its Roots supercharger. Exciting as the new Cobra is, we deemed it too expensive and clearly in another performance league to include in this examination.
The threesome tested represents an interesting mixture of late-model Mustang performance. The Cobra has a Four-Valve engine rated at 320 hp at 6,200 rpm, while the Mach 1's Four-Valve achieves 305 hp at 5,800 rpm. The Bullitt Two-Valve also uses the iron modular block, but it has smaller, lighter Two-Valve heads for the lowest center of gravity even if it's a bit heavier on overall engine weight. The Bullitt makes 265 hp at 5,000 rpm.
Torque is also an interesting com-parison. The Cobra is built to rev and makes 317 lb-ft of torque at a relatively high 4,750 rpm. A quick trip around the block shows the Mach 1 has inherited the Four-Valve's rev-gene, but cam and intake tuning produce 320 lb-ft of torque at a lower 4,200 rpm. The Bullitt, of course, doesn't pretend to rev like its Four-Valve cousins, but it does muscle its way in with 305 lb-ft of torque at a streetable 4,000 rpm.
All three cars use the identical PBR-based 13.1-inch front brake package, and the Mach and Bullitt wore the same-style Goodyear Eagle ZR45 tires.
Gathering the cars took some effort. The Mach 1 was as easy as a call to Ford Public Affairs, but the Bullitt and Cobra are not current production cars and thus are extinct in Ford's media fleet. Hunting around, we ended as usual being helped by old friends. Miles Cook, who worked with us at Super Ford and is now the technical editor at our sister publication Mustang Monthly, was eager to pit his personal Bullitt against the Cobra and Mach. Miles had not quite 16,000 miles on his blue Bullitt and was still enjoying it in dead-stock form, so it was a shoe-in to represent the Two-Valve crowd.
The Cobra was a bit more difficult. We really wanted one of the relatively rare '01 cars, one built after "the fix," still totally stock and belonging to an owner willing to have his pride-and-joy rung to the max on the test track. Yeah, right. But BBK had a '99 Cobra on hand with what turned out to be only three modifications: a shifter, BBK springs, and a cold-air kit. The shifter would not be a meaningful performance issue, the cold-air kit we weren't sure of, and the springs would definitely show up in the handling portion. On the other hand, the car was sporting a new warranty engine-the original had split a gizzard-so its power output would be like a fresh Cobra.
The Cobra had one other change definitely worth mentioning-BFGoodrich G-Force T/A KDW tires replaced the stock Goodyear Eagles. Still in 245/45ZR-17 size, the Goodrich tires are definitely performance tires, although not track-biased ringers with a treadwear rating of 100 or so. Going the other way, these tires looked to be in good shape, if a bit dried out. Call them middle-aged.