Tom Wilson
August 1, 2003
Photos By: Randy Lorentzen

Horse Sense:
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.

Our formal testing was done by the Motor Trend road testers at California Speedway in Fontana, California. This gave us state-of-the-art radar test data at what is now MT's standard test facility. Dodging rain, we ended up with a beautiful day with standard temperatures, no wind, and sea-level barometer-in short, little to skew the numbers.

We also conducted informal testing-piling on the miles while picking up and dropping off the cars, some extended time in the Mach and Cobra for real-world evaluation, and, finally, rolling start Second-through-Third gear acceleration tests with all three cars to see how they fared in typical user modes. Standing-start blasts to more than 100 mph are not typical mission profiles for street cars, after all.

Let's begin by taking a look at the formal tests.

The heart of a comparison such as this is how each engine moves its car. Always a good sign, opinions among us were varied in the beginning as to who was quickest, and it was an amazingly close race all the way. Regular test driver Chris Walton did the honors, with the following results.

0-30 Mph0-60 Mph1/4- Mile
Cobra2.1095.2513.{{{62}}} @ 105.2
Bullitt1.7675.1513.59 @ 102.4
Mach 11.7674.7013.19 @ 106.7

How's that for surprises? Who'd have thought a Cobra was slower than a Bullitt? And dig how the Mach 1 is more than a half second quicker to 60 mph than the Cobra-no wonder SVT put a blower on the '03 snake.

Some considerations need to be made, however. For starters, Cobra acceleration didn't benefit from the slightly shorter, stiffer BBK springs. These inhibit weight transfer, making the already relatively high-strung Cobra a tougher customer off the line. Chris spent a little extra time finding what this Cobra wanted, saying, "It turns out this Cobra likes a little wheelspin and doesn't produce any axlehop. About 3,200 rpm was all it needed to break the tires loose, but unlike the stock tires, these didn't spool up uncontrollably-they were tractable and responded to 'pedaling' the throttle. Short-shifting one-two and [the] two-three [shifts] (at 6,000 rpm) made the best numbers. I let it rev in Third to make the quarter-mile."

The overachiever of the bunch is clearly the Bullitt. Its Two-Valve engine is obviously biased to produce more low-end thrust than the Cobra-and maybe equal the Mach-and it shows in the 60-mph time. The relative lack of top-end charge is also indicated by its 3-mph-slower trap speed, even if this was a stellar set of Bullitt acceleration numbers. Chris' take on it was, "I had one magical launch that made this the quickest and fastest Bullitt we've seen yet. A 1.767 0-to-30 time exactly matched the Mach 1, but then the Mach 1 pulled away. Still, Miles owes me a lunch for getting his car deep into the 13s!"

And then there is the Mach. Clearly Ford has been running Four-Valves on the dyno-you simply can't make good quarter-mile times or especially mph without horsepower. But the Mach 1 is also the most softly sprung of the three cars here, with good weight transfer to plant the rear tires and no danger of wheelspin from the live rear axle. As Chris put it, "This was the fastest of the three to launch. I could dial in as much or as little wheelspin as I wished with my big toe. The shifter felt better-more precise than I expected-and I like the metal [shift] knob. It was also a surprise to find some useable power in the upper end revs-she just pulls and pulls. However, the best run was with a softish launch and short shifting at 6,000 rpm."

There's no single test that can objectively measure the subjective, dynamic quality called handling. The two standard tests are the skidpad, which shows the car's ultimate grip in a steady turn (largely a tire test), and the slalom, which illustrates how well the car can transition from turn to turn. Because the slalom is conducted by accelerating through a series of cones, secondary issues come into play. They are how controllable the horsepower is, and just how much thrust is on tap, as it takes power to push tires around the cones and accelerate out of the final gate to the finish line.

With our trio the skidpad was close because the Mach and the Bullitt were both on the same tire-and in any case, all three Mustangs employ the same size tire, share the same wheelbase, relative weight, weight balance front-to-rear, and other basic chassis characteristics. Thus, we have the basically identical 0.84 g scorings for the Goodyear-shod Mach and Bullitt, and the slightly behind 0.83 g measurement for the Goodrich-equipped Cobra.

In the slalom it was a completely different story. Here the Cobra shone, due largely to its modifications. Chris' critique says it all. "Besides the '02 Saleen S281-E I tested in October 2001 at 68.9 mph, this is the quickest Mustang through the cones at 67.1 mph. It can't be just tires. Did somebody change bushings, steering gear...? The car was glued to the pavement and didn't push at all. Nice!"

Well, yes, it's those lowering springs again. That slight change in the center of gravity, and more importantly, stiffening of the spring rate, really showed up in the slalom. This is typical of the more softly sprung SN-95 Mustangs that really pick up left-right-left prowess with an increase in spring rate.

Chris was also impressed with the Bullitt and its 66-mph posting. "Of the three we tested, the Bullitt 'felt' the best ... was the most confidence-inspiring. The front wasn't heavy, the rear wasn't heavy, the whole car felt poised and balanced. Also, is it lower or does it have a lower center of mass? It feels like it. It'd drift all four corners like a BMW. Saaaweet!"

Obviously we weren't telling Chris anything about these cars... and what he was feeling was the Bullitt's lower front center of gravity thanks to its iron block and lighter Two-Valve cylinder heads.

A definite notch in arrears was the Mach 1 at 63.5 mph. This was no surprise to us given the Mach's soft street ride and general plushness. Still, it wasn't falling all over itself like a Town Car. "Typical for a Mustang, it runs out of tire before it runs out of poise," said Chris. "It had a far crisper turn-in than the Cobra, but not as good as the Bullitt."

Brake testing ABS-equipped cars is fairly easy stuff-just stand on the pedal until the final lurch to a stop. Much depends on the ABS, just as it does in the real world, and here the Cobra experienced difficulties. "Something isn't right with a 134-foot stop from 60 mph," Chris said, "especially with the KDW tires. Could it be the ABS expects less grippy tires and can't cope?" Perhaps, although there was no lock-up, ABS warning light, or other adverse signs. The 100-mph stop was also huge at 369 feet. If it were our car, we might try rebedding the brake pads or deglazing the discs.

Even stranger, the Mach 1-fresh out of the press fleet and with less than 1,200 miles on the odometer-was also in trouble. "We'll have to say you get one good one and then all bets are off," Chris said. "The second and third attempts locked up both front wheels! We shut the car off, restarted, and the ABS mysteriously rebooted. No warning light, no warning at all-just a plume of smoke and two skid marks." The 123-foot and 357-foot stops are par for late-model Mustangs-which is to say they're not world-class thanks to the nose-dragging, tail-high chassis dynamics-but that's what we've seen from other 13-inch PBR-braked Mustangs using street pads and tires.

Once again the Bullitt outshone its more illustrious cousins. Stopping from 60 mph in just 118 feet and from 100 mph in 338 feet-that's two-and-half car lengths less than the Cobra-the Bullitt also earned nice praise from Chris. "This 118-foot stop from 60 mph backs up our previous 119-footer from Motor Trend's '01 Bullitt test, but the 338-foot [stop] from 100 is way better than a 361-foot stop a year ago. It took three stops before distance began to increase."

Clearly, with all three cars sharing the same brake package and two on the same tires, we'd expect them to stop more closely to each other than this. The Bullitt exhibits the stopping power we'd expect from any of these cars with a properly functioning brake system. Some attention to disc and pad maintenance (and the ABS in the Mach) ought to do the job.

On the Street
It's all about feel on the street, not numbers, so to get that feel Miles and I paired up and "street raced" from 25-mph rolls beginning in Second gear. Using handheld radios to count down the start, we began with the Mach 1 and the Cobra. The Mach jumped to a one-plus car lead and pulled ever so slightly on the Cobra. I was in the Cobra and couldn't even begin to even things up with the Mach. Interestingly, the Mach went through Second gear, then shifted into Third and maintained its distance on the Cobra. It seemed as though Miles short-shifted the two-three slightly, but he was working with a lower redline too. I stayed in Second in the Cobra, and just as I was nearing redline in that gear, I began to pull a tad on the Bullitt. But by then the test was over. After all, if a street car can't do the job in two blocks, it's not going to, and we have quarter-mile numbers if you want to know how a proper drag race would turn out.

Then we turned around and went again. This time the start was more even, and the two Four-Valve cars pulled evenly. We both stayed in Second gear, and there was no change in position. Still, the Mach got the initial jump of about a quarter car length and stayed there. The Cobra could do nothing about it.

Miles and I concluded the first start had been jumped by him, or late by me. Still, the cars seemed dead even, so anyone street racing these things better be an ace on the start, because he's certainly not going to chase down the other car with it.

Next, I got in the Mach and Miles got in his Bullitt. We still used the radios to count down and aimed for 2,500-rpm, Second-gear starts. The Mach pulled the Bullitt by at least a car length, and that was that. We did this twice, and the second time I lifted and got right back on it again on purpose just to see if the Bullitt could make ground if the Mach 1 driver flubbed the start. This let the Bullitt out in front a tad. The Mach did start to pull it, though not really enough to be totally comfortable in a two-block knife fight. However, if the race had any length to it, the Mach would win every time.

Because the Cobra and Mach were so even, we didn't take the time to pair the Bullitt with the snake.

So What's Your Point?
In the bull session after our "street races," Miles was justifiably proud of his Bullitt and happy it stood up against the Four-Valve competition so well. Obviously, it won't run out the back door from the deep-breathing Four-Valves, but a sharp Bullitt driver will not be embarrassed from a lack of power and clearly has no worries in the turns. Bullitts, even the nongreen machines (Miles' car is 1 of only 700 or so blue Bullitts, so it could have some rarity value in later years), are sharp, handsome, purposeful cars, too.

It's also important that Miles' Bullitt has the best street ride of this threesome. It's more plush than the stiff-gaited Cobra with its aftermarket springs, but it's firmer than the Mach 1's musclecar softness. It has the just right combination of ride, steering response, and cornering for daily driving when you have to and fun when you want to. And while none of these Mustangs sets the mark for modern cabin comfort or utility, the Bullitt interior offers classic, old-boy-club comfort without trying too hard with overstyled trim. And let's not forget the Bullitt was easily the leader when comparing showroom floor prices. It's king of the Two-Valves.

The Cobra? As Editor Turner says, "There's nothing wrong with that car that a set of 4.10 gears won't cure." Amen, brother. With that one small addition the Cobra would out-snap the Mach, annihilate the Bullitt, and still have the rpm to rip down the freeway. However, even with stock gearing the Cobra prevails anywhere the rpm can be kept spooled up and the momentum rolling-a road-racing track, in other words.

In the end, though, these midyear Cobras must be regarded as specialists. They're rpm-dependent and a bit heavy. While the IRS does smooth prominent bumps and occasionally saves your bacon on heaved pavement, the Cobra driver always has a sense of substance-a battlewagon demeanor of mass, power, and presence.

Given the experience with the earlier cars, Ford definitely has refined the mix in the Mach 1. It really has no bad points, combining the torque of the Two-Valve Bullitt with nearly the top-end horsepower of the Cobra, to arrive at a powertrain that both daily drives and races with authority. There's the fun of the retro styling, the gee-whiz of the hoodscoop for your friends to admire, a pillowy ride, and definite value in the pricing.

Pleasing Mach 1 details keep coming too. The exhaust note is near perfection-a bit roary but missing the boom and without a hint of drone. Light throttle pressure does the lane-change trick on the freeway, and you can even trade some performance for an automatic transmission if you insist.

All three of these Mustangs are Big Units, but time shows they keep getting better. It makes us wonder what's in store.

The Hairy-Chested Cobra
We couldn't resist. After our three-car test, Ford turned us loose in an '03 Cobra. With 390 Roots supercharged horsepower and matching torque, a six-speed transmission, and a price tag to match, the latest thing to slither out of the snake pit is ferociously fast and retains the family trait of weightiness, power, and presence. Still the ruling Mustang, SVT's Cobra is a high-dollar, no-excuses Mustang. It's no ballet dancer, but like a fullback it is fabulous at sprinting out interstate miles and muscling traffic at the light, yet it still has enough agility for back road fun. With its manly clutch effort, a bicep-building shift lever, and the need to consider its considerable mass when contemplating a round of catch-and-toss cornering antics, the flagship Cobra is definitely not for the limp-wristed.

The All-Around Measurement
While most track tests isolate a single performance parameter, accelerating from a stop to 100 mph, then braking to a stop again does sample power, braking, and some handling, and is thus a fair look at how balanced a car's performance personality is.

In our trio, the Mach 1 definitely has the best combination of torque and horsepower, brakes well, and has the softest, most weight-transferring chassis. Looking at the data, it's clear the Mach's engine made up for the 0.2 second its chassis and brakes lost to the Bullitt, and with the Cobra flunking the braking test, this one was a walkover for the Mach 1.

Mach 1
100-0, sec = 4.85
0-100-0, sec = 16.785

100-0, sec = 4.63
0-100-0, sec = 18.022

100-0, sec = 5.10
0-100-0, sec = 17.892

Just Checking
Because the BBK-sourced '99 Cobra tested for this article was slightly modified, we went to the archives to consult Motor Trend's last naturally aspirated Mustang Cobra test to see if there were any meaningful differences. The previous test was an '01 Cobra from Ford's press fleet, and the acceleration numbers are essentially identical to the '99 run in this test, so no worries there. The slalom was definitely slower in the earlier test; that's accounted for by the BBK lowering springs. Likewise, test driver Chris Walton believed the '99 Cobra brake system was suspect, and the '01 test verifies his hunch with stops much more in line with the Bullitt and Mach 1 in this test. No skid pad testing was done on the '01, so those numbers were not available.

0-60 Mph1/4-mileLateral AccelSlalom
'01 SVT {{{Mustang Cobra}}}5.28 sec13.66 @ 104.9765.25n/a
60-0 Mph{{{100}}}-0 MphRPM @ 60 mphSlalom
'01 SVT Mustang Cobra125 ft349 ftn/an/a

Another View
Although I own the Bullitt that was used for this comparo-and I'm quite partial to its subtle good looks-I was impressed with the other two cars as well. Once the dust had settled, it was clear that all three of these Mustangs excelled in specific areas. It turns out the '03 Mach 1 was the clear victor on the quarter-mile with its newly updated DOHC engine. Our representative '99 Cobra was the champ in the slalom, due in large part to its BFG KDW tires and lower ride height. And the '01 Bullitt seemed to have an interesting overall balance that helped make up for its lack of beans in comparison to the Mach 1. In a surprise, the Bullitt also stopped in the shortest distance, even though all three cars have the exact same brakes.

There are a few things to note about each car. The word is out on the street-the Mach 1 is simply a dragstrip hero with cars generally running in the mid to low 13s. It's truly a naturally aspirated Mustang that can run door-to-door with any stock F-body you might come across on the boulevard. Wait until the superchargers start turning up on these bad boys.

The Motor Trend staff kept saying all day that the Bullitt is the best-balanced car of the three and would clean up shop in the slalom. It turns out this theory is accurate as the Bullitt was right on the heels of the Cobra, which was shod with much grippier tires than the Bullitt. In turn, both the Bullitt and the Cobra blew the doors off the Mach 1 on the slalom course. It's clear Ford has oriented the Mach toward being more of a straight-line car than the others, though it still drives quite nicely on the street. The MT crew says if all three cars were on the exact same tires, the Bullitt would leave the other two in the dust with no problem.

And the Cobra? Well, it's a Cobra. That means-on paper at least-it has the most exotic bones of the three, the most notable being the independent rear suspension. But the particular car we had turned out be a bit of an enigma. While we wanted a totally stock example, this '99 had different tires, a lowered suspension, and a new engine installed under warranty after the original mill gave up the ghost. Bottom line? Ninety-nine and '01 Cobras will always be excellent beginnings for the buildup of a seriously fun SN-95 street (or open-track) car since they were the only ones built with high-winding, naturally aspirated power and IRS.

As for me, although I'm jealous of the Mach's distinct power advantage (and don't get me started on the '03 Cobra), I'm not going trade my Bullitt for a Mach 1. The subdued looks of the Bullitt win me over, even though the Mach does look cool. Besides, a little boost on the ol' Bullitt will cover those pesky Machs with no trouble, and it would then run with a (stock) '03 Cobra to boot. - Miles Cook

At the Track

0-30 Mph0-60 Mph1/4-MileLateral AccelSlalom
'99 SVT Mustang Cobra2.10 sec5.25 sec13.62 @ 105.20.83267.1
'01 Mustang Bullitt1.76 sec5.15 sec13.59 @ 102.40.8466.0
'03 Mustang Mach 11.76 sec4.70 sec13.19 @ 106.70.84963.5

60-0 Mph{{{100}}}-0 MphRPM @ 60 Mph
'99 SVT {{{Mustang Cobra}}}134 ft369 ft1,800
'01 Mustang Bullitt118 ft338 ft1,800
'03 Mustang Mach 1123 ft357 ft1,800