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Mach Won: A Mach 1 Gets Vortech's Blower
When hanging Vortech's blower to a Mach 1 we found some impressive results - it crushed a stock '03 Cobra!
During these happy days when exciting specialty Mustangs sprout on showroom floors like so many spring mushrooms, the Mach 1 has proven a favorite of ours. With a willing engine, an easy-to-work-with chassis, and a price that's obtainable by at least a few of us, the Mach is a mighty temptress of our car-buying budget.
Then along comes Vortech, doing what it does, which is to hang centrifugal superchargers off everything save tree limbs, which now includes Mach 1 Mustangs. Talk about temptation.
Developments such as these lead to ruminations around the 5.0&SF water cooler, and it was thus decreed that closely examining Vortech's enhanced Mach would be a good thing. There were, after all, a few questions, such as how does Vortech plumb its blower into the ram-air air path? How much power does it make? Is it fun to drive? And perhaps as something of a cliche now that we've tested one seven ways to Sunday, how does it compare to that modern benchmark, the '03 Mustang Cobra?
Horse Sense: Just as we hit deadline, we learned our friends at Motor Trend had run the Vortech Mach 1 through their test regimen. Make sure to read the full test results in an upcoming issue. Anyway, at normal operating temperature, the Vortech Mach laid down a blistering 11.96 at 121.16 and went from 0-60 in 3.88 seconds. That positively blows away the '03 Cobra we ran through the same regimen back in the Jan. '04 issue. It registered only a 13.09 at 110.82 and went from 0-60 in 4.9 seconds. It looks as if only modified '03 Cobras can run with the Vortech Mach.
Aside from sitting in the never-ending Los Angeles-area gridlock while shuttling test cars around, getting the answers proved relatively easy. A call to Ford produced the same yellow Cobra we'd previously tested ("Snake Prize," Jan. '04, p. 40), and the rest was done at or near Vortech's facility northwest of Los Angeles. A quick session on Vortech's Mustang chassis dyno revealed the power and torque curves of these two different supercharged Four-Valves, followed by a trip across the local truck scales and then an enjoyable session of side-by-side, rolling-start blasts to see how the power curves came out in the real world.
Great Straight from Ford
As a point of departure for this test, let's recall how enjoyable the Mach 1 is stock. With a naturally aspirated, free-revving, 305hp Four-Valve V-8, a five-speed transmission, and a live rear axle, the Mach is a powerful combination of GT practicality and high-dollar Cobra-esque power and sophistication. Priced in the $28,000 neighborhood, Machs were actually selling for around $21,000 after incentives at our deadline--not chicken feed, but obtainable, especially when compared to the $35,000 Cobra.
Ford gives the Mach 1 a soft spring and shock tune for an easy ride and rapid weight transfer at the dragstrip, yet the strut front and live rear axle suspension is easily modified with any number of aftermarket options, if desired. The interior has difficult-to-read, retro-faced instruments, but the seats are comfy, and a bit of muted bright tones around the instrument cluster and center console relieve what could otherwise be black boredom. The Shaker hoodscoop is unique, and the power is quick and easy.
Mach 1s nominally breathe through a standard, inner-fender inlet, conical air filter enclosed in a box, along with the standard air meter, throttle body, and associated air tubing--the typical Mustang air path, in other words.
To this, Ford has added a Shaker hoodscoop. Because the standard snorkel inlet to the air-filter box is never closed, if pressure were to exceed ambient in the airbox, it would back-track out the snorkel inlet. A slight pressure rise could be detected with sensitive laboratory instruments, but nothing practical would come of it. But, hey, the hoodscoop is fun and no one gets hurt.
As for our subject Mach, to the already impressive stock mechanicals, owner Trevor Kaplan, once Vortech's marketing manager for sport-compact cars but now on to other jobs (and faster cars), has added a beguiling mix of aftermarket improvements. The supple-but-occasionally-imprecise stock suspension was completely replaced by the more-supple-yet-definitely-precise Griggs
Racing GR-40 kit, including coilover shocks. Trevor opted for a stock-style- ride spring and shock tune to preserve daily driver comfort.
Baer Brakes are found in the wheelwells for fade-free stopping, with Halibrand wheels setting a surprisingly well-considered retro-tech style to the machine. The Toyo tires are Proxes 275/35-18s with an amazingly low treadwear rating of 40 to ensure pliant traction at all times. Inside, Auto Meter Phantom gauges pick up the silver metal theme, while VinylMayhem did the tasteful add-on graphics.
Under hood are Denso Iridium spark plugs--a proven aid in avoiding misfiring in supercharged engines, along with a Bassani X-pipe and after-cat exhaust system.
Vortech's Mach 1 Kit
And then there is the Vortech V-1 SQ supercharger installation, for which Trevor's car is acting as the guinea pig. For its '02-'03 Mach 1 kit, Vortech began with its existing '01 Mustang Cobra kit, which means the blower installation is readily familiar to Mustang enthusiasts as few changes were required. As always, the Vortech buyer has his choice of a standard output (around 7-8 pounds of boost) or the high-output variety (10-11 pounds of boost). The high-output has proven most popular.
Actually, there are two Vortech kits for the Mach 1. The standard kit is everything--supercharger, aftercooler, fuel pump, and so on--minus anything to do with the Mach 1's ram-air hardware. In other words, the standard kit supercharges the Mach, but simply ignores the hoodscoop, leaving it there for looks.
Optional is the Functional Ram Air kit. It adds those parts necessary to connect the air scoop into the blower's intake path. In a bit of lawyerly labeling, the Functional Ram Air kit does deliver all the function the stock Ford ram-air arrangement does, which is to deliver what air may go down the scoop into the general vicinity of Vortech's conical air filter.
Getting back to the standard Mach 1 blower kit, as expected, the blower sits on a Vortech-supplied bracket, facing the engine so as to share the serpentine drive belt.The oil pan is punched and fitted with an oil drain-back line from the blower. The battery is relocated to the trunk to accommodate the aftercooler reservoir. The aftercooler radiator and electric water pump are fitted to the lower radiator support. Iridium spark plugs are highly recommended. A 255-lph fuel pump replaces the stocker in the fuel tank. The 38-lb/hr injectors are swapped for the stockers. And the kit comes with a voucher that is returned to Vortech for a custom-calibrated computer chip. The kit is complete and well detailed, which also means it retails in the $6,000 range and will take the home-shop enthusiast all weekend to install. The battery relocation and dropping the fuel tank for pump installation are meaningful jobs by themselves, after all. As always with Vortech, the installations are clear and complete.
As for the Functional Ram Air option, that kit was still under development at our deadline, so final materials, dimensions, and pricing remain undetermined. What's involved, however, is a new tray--or lower section--of the hoodscoop. It has a large outlet and tubing leading down to Vortech's open element air filter in the right inner fender.
There has been talk inside Vortech of making a sealed box for their air filter, along with a trap door to seal the regular air inlet whenever the hoodscoop supplies the majority of air, but at this point that's just talk.
Hitting the Rollers
We began our test day by running the Mach 1 on the chassis dyno. This was done on Vortech's Mustang dyno while we observed. All went well and we soon had our dyno results.
The first official pull netted 362 hp at 6,850 rpm and 328 lb-ft at 5,050 rpm, while the second pull showed 371 at 6,700 rpm and 327 lb-ft at 5,050 rpm. That's a gain of 9 hp and a loss of 1 lb-ft of torque as the oil warmed up.
If these numbers seem low, they are. That's because the Mustang dynos--which load the car to replicate its weight going down the road--religiously read substantially lower than the more widely known inertial Dynojets--as much as 40 hp less at times.
Lance Keck, one of Vortech's dyno operators and the guy who'd been dyno'ing the Mach 1 for days, said the car would make another 5 hp if we ran it to death warming the oil, but that was about it. So we pulled the Mach and strapped on the Cobra.
Right out of the gate, the Cobra made 319 hp at 6,400 rpm and 306 lb-ft of torque at 3,850 rpm. The second official run saw nearly identical numbers-- 319 hp at 6,400 rpm and 309 lb-ft at 3,800 rpm.
We knew the Roots-type blower on the Cobra would make excellent torque down low and would fall behind the Vortech at higher rpm, but we weren't quite ready for such a large difference. The Cobra torque curve simply sky- rockets off idle and lays down gently with advanced rpm, while the Vortech centrifugal supercharger does just the opposite. Comparing torque and power curves, the Cobra and blown Mach just about make an even trade for area under the curve. So, the Cobra is about 50 hp shy of the Mach at the top end, but the Mach trails the Cobra by 90 lb-ft of torque in the 2,400-3,100 rpm range.
The other way of looking at it is the Mach is behind the Cobra up to 4,000 rpm. But, whereas the Cobra makes relatively flat curves all the way across the tach, at 4,000 rpm the Mach's horsepower curve simply soars away from the Cobra. As for torque, the Mach has a nice little bump of extra torque compared to the Cobra between 4,300 and 5,300 rpm--that's how it outpeaks the Cobra in torque.
Vortech was surprised by the strength of our press-car Cobra. The company had tested two private-owner Cobras previously, both of those putting out high-200hp figures on the company's Mustang dyno. Our car was maybe 30 hp stronger than these other Cobras. So a STAR tester was hooked to the Cobra to read out its boost and ignition timing. The Cobra boost started at 7.2 pounds at just 2,200 rpm, an impressively low rpm for such manifold pressure. By 2,600 rpm, it was making 8 pounds. It peaked at 9.5 pounds at 4,300 rpm, then fell to 8.6 pounds at 6,380 rpm, which all sounds correct. The ignition timing was a stout 23 degrees around the power peak, another typical Cobra value. So, it would seem we had a good, fresh, strong-running Cobra.
To the Scales
Our next stop was the truck scales. Modern cars are heavy, as the following chart shows.
Front: Cobra - 2,080; Mach 1 - 1,900
Rear: Cobra - 1,580; Mach 1 - 1,560
Total: Cobra - 3,660; Mach 1 - 3,460
All figures are in pounds.
Both cars had a half tank of fuel and were weighed without drivers. More importantly, the Mach 1 benefited from its Griggs suspension, which Griggs Racing said should account for a 65-pound reduction on the front axle. Still, at 200 pounds, the Cobra's weight penalty was significant in this test. Even without an aftermarket suspension on the Mach, the Cobra would definitely outweigh the Mach.
It's interesting how theory often goes under the bus when the pedal hits the metal. Much of this seems to be less than expert prognostication by those involved--namely us--and some of it is how much perception and emotion count compared to columns of numbers on a dyno sheet.
Going into the side-by-side trials, everyone involved just knew the Cobra would lunge to an immediate--if modest--lead, then be passed by the Mach as the contest continued. We were wrong.
In reality, with any rolling start, the Mach walks away from the Cobra, end of story. The only exception was from a slow, nearly lugging Third-gear start. Then the Cobra pulled a fender on the Mach, only to have the Mach trot on by within a second or so. Even when we cheated and started the Cobra in First and the Mach in Second, it was Mach all the way. The Mach's advantage held as speed rose. Believe us, the Cobra was never going to run down this Mach no matter how far the pair ran out the back door. Only if the Mach 1 pilot was asleep and the Cobra driver lying in wait would the outcome be in any question, and then only for a short time. So, the bottom line was both cars would begin accelerating, and for the first half second there was no relative motion. Then the Mach would begin steaming ahead, constantly pulling a lead on the Cobra.
We did not attempt any standing-start runs, but the results are predictable. The Mach, with its live rear axle, could use the more aggressive launch, and our particular Mach, with the torque arm rear suspension, would simply plant the rear tires and leave. The Cobra's IRS is sensitive to pavement characteristics, so it may have allowed a modest launch or wheelspin, depending on traction. So the Mach would win again.
Seat of the Levi's
Once again we're reminded how Mustang Cobras can feel heavy and slightly unwieldy around town or on tight secon-dary roads. It's a perceptual thing, coming from cues as subtle as the thick steering wheel, the somewhat high steering effort, the clunky shifter action at parking-lot speeds, the shifter being too far forward, the heavy clutch pedal, and even the overstuffed bolsters in the seats that cramp all but the smallest drivers.
The Mach 1, by comparison, feels lighter than its missing 200 pounds would suggest. Of course, our test car did have greatly improved suspension geometry, but with a lighter clutch pedal, a smooth shifter, a thinner steering wheel rim, and--yes--lighter, more-alive steering, the entire car came off as eager and willing. The louder Bassani exhaust didn't hurt, either.
But most of all, there is the power delivery. The refined--dare we say formal--Cobra has a rheostat powerband. Turn it up and you get more; dial it down and you get less. But the sound and the push in the back stay basically the same. It's not a bad sound, especially the arousing wind whistle from the Eaton blower at full throttle, and the push in the backside is plenty healthy. But compared to the centrifugal Mach, it's the brother that gets straight As and stays out of trouble.
Vortech's Mach starts off with enough snap to hold your attention, then piles on the power in an escalating rampage. It's going to go fast and it won't let you forget it. The combination of a hair more gearing and compression ratio, as well as the wheel blower's logarithmically increasing air delivery, makes the Mach feel more explosive than sveltely powerful like the Cobra. And given the Vortech SQ blower's quiet gear train, there is no whining to put up with at idle either. It's a lusty combination.
The Long Haul
If we have a caveat about the Vortech Mach, it's long-term durability. Unlike the Mustang Cobra, which was engineered from the get-go by Ford as a blower engine with an iron block, stupendously strong Manley connecting rods, and forged pistons, the Mach Four-Valve is definitely built on the light side.
Mach 1 engines are not simply Cobra engines wearing a party-hat hoodscoop. To reduce runaway parts counts in the modular engine line, and thus increase interchangeability from engine to engine, Ford has tidied up things in the parts bins. So, while the Cobra continues with the heavy-duty, high-cost innards, the five-speed Mach 1 engines use a low-rent cast piston, a pressed-metal connecting rod, the good eight-bolt Cobra crankshaft, and an aluminum block. Built to sparkle as a naturally aspirated engine, the Mach 1 Four-Valve has 10.25:1 compression pistons, which provide sporting amounts of cylinder pressure for themselves and their con rods in stock form.
What's more, Mach 1 fuel systems rely on a single fuel pump, along with smallish (for the fuel flow) fuel rails. Keeping the fuel tank at least half full helps--aftermarket fuel rails and somehow opening flow to the fuel pump inside the tank are much better.
Bolting a blower atop this combination thus produces excellent power at relatively modest boost pressures, but it must pay a price in long-term durability and has precious little in the way of reserve strength should detonation occur. Driven with a modicum of restraint--uh huh--and fed a steady diet of high-octane pump gas, we'd wager the blown Mach is good for many tens of thousands--likely 100,000--detonation-free miles. But rodeoed at every light and it's more than likely a piston or rod will let loose. Our advice is to buy the aftercooled option, run good gasoline at all times, and take it easy in hot weather. This is one combination with which you want to avoid detonation.
It's amazing how complex and well-engineered the Ford performance hobby has become since the innocent 5.0 days. Vortech has been there for nearly all of it, and this newest Mach 1 kit shows all the detailing and sophistication for which Vortech has become known. That it can kick a stock Cobra squarely in the teeth shows just how excellent is its performance. Clearly this is a mid-12-second car in the hands of even the average stroke. That it comes from a bolt-on Mustang with a blower kit installed is remarkable.