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2011 Vortech Supercharger Kit Test - Deja Boost
It's 20 Years Later And A Different 5.0, But Once Again Vortech Has A Centrifugal Blower
It's appropriate that the first '11 Mustang GT supercharger we should examine is Vortech's. The company started, and was for all practical purposes, made by the original 5.0 Mustang, and the two names have been linked ever since. While the first Vortech Mustang kits were the work of a talented but fledgling company, Vortech is now a mature speed corporation still blessed with talent, but enjoying the full range of corporate capabilities. Among the greatest of these is 20 years of supercharging Mustangs and an especially strong production capacity emphasizing accuracy.
It's understandable, then, that Vortech had an appropriate '11 Mustang GT supercharger-the self-lubricated V-3 in Si-Trim-already spinning away under the hood of Three-Valve Mustangs. All that was necessary, at least from a hardware standpoint, was to package it to the new Coyote engine. This was done by Vortech technician Peter Waydo, who took us through the new kit's installation, testing, and general layout.
The tuning is a different kettle of wiring, of course, and was still on-going by tech Lance Keck during our first look at the new Vortech kit. As always, Vortech is selling the new supercharger with a street-legal, conservative 91-octane tune. There is plenty of racing potential here, and the bigger YSi and Novi 2200 blower heads bolt into this bracketry as upgrades-but the standard kit is designed for trouble-free street use.
The first thing an old Vortech hand will notice is the blower's handsome black finish. Officially this is a one-time specialty treatment commemorating Vortech's 20th anniversary and is limited to the first 50 (or 100, depending on who you talk to at Vortech) '11 Mustang GT kits. But it's so sharp you know market demand will have Vortech building black blowers for the next 20 years in addition to their usual satin and polished offerings. If you like the look, let Vortech know.
Under that black the familiar V-3 blower is unchanged and is sold with equally familiar Si-Trim, as it is on the Three-Valve kit. The mounting bracket is all new, naturally, and works with the outer of the two stock six-rib drive belts. The stock Ford belt routing is unchanged, with only extra length in the new belt to accommodate the Vortech idlers and blower pulley. Belt wrap around the blower pulley is downright circumferentional to coin a word, and the mounting plate appears robustly rigid. No stock Ford accessories are relocated or deleted, the Vortech proving purely an add-on.
As expected, the stock intake manifold and throttle body are left intact, although the throttle body is inverted and spaced forward for blower clearance. Concerned about possible driveability or power issues, Vortech tested the re-positioned throttle body on their otherwise stone stock test mule before starting blower development and found absolutely no problems.
For street use, Vortech retains the stock air-filter-box assembly to avoid any complications with the California Air Resources Board and their insistence on maintaining the stock hydrocarbon trap in the air filter lid. An off-road-only underhood "cold-air inlet" with the usual cone filter and air dam will be offered for racers and should be worth 10-15 hp depending on the final tuning.
A big change for Vortech (but not sister company Paxton), is a move to air-to-air charge cooling from Vortech's traditional water-to-air system. Packaging is the cited reason; there just isn't room atop the engine compartment to fit a heat exchanger there. We think cost reduction may have played a role as well, but no matter, air-to-air charge cooling is effective, packages easily in the '11 GT, weighs less and should help holds costs, so we're happy to see it.
Given the daily driver nature of this Vortech kit, plus what seems an intent by Ford to someday provide forced induction in the Mustang, the stock fuel pump, filters, lines and rails proved plenty large. Only the fuel injectors require a step up to the tried and true GT500 units. Electronic tuning is done via an SCT hand-held flash tuner hooked to the electronic data port under the dashboard. As always, Vortech demands a stock compression ratio and 91-octane-or-higher premium fuel. East Coasters with ready access to 93-octane premium can gain an additional 30 hp with custom tuning.
Thanks to the intricacies of the parts supply pipeline, divining the street price of Vortech's soon-to-be-released '11 Mustang GT kit requires some crystal balling. The suggested retail-a price no one pays-is $5,995.95. This is identical to the same system if it were polished and more than if it were garden variety satin. Satin pricing had not been set at our press time.
Squinting a little, we'll guestimate the real-world street price of the black anniversary '11 GT kit to hover at $5,475. Expect the same pricing for the eventual polished kit, and about $5,250 for a satin kit. Another guess is when the satin and polished kits will be released. The black anniversary kits will definitely be available by the end of November 2010, and we'll wager the satin/polished versions will show by March 2011, possibly sooner.
The other option is a tuner kit. That's a blower kit designed for pro shops that prefer to do their own tuning, so they don't want, need or get a flash programmer, fuel injectors and other fuel system bits in a tuner kit. In short, it's just the mechanical portion of the blower kit and typically costs approximately $1,000 less than the full kit. But obviously the installed cost will still reflect aftermarket fuel injectors and custom tuning.
All told, the '11 GT Votech is a moderate installation job that should take at most one shop day. Home installation by experienced enthusiasts is no problem. With its relatively modest low-rpm power increase and strong top end charge, the Vortech is a good partner for the gent wanting a civilized around-town driver along with extra snort when pushing hard. It's also a smart choice for any sort of road course work-open-tracking or racing-because the power is easily hooked up, the rpm can easily be kept high on the track and weight gain is less than a positive-displacement blower.
Drag racers may find the Vortech revvy personality helpful, too, depending on how much traction their class allows, but they may miss icing the old water-to-air charge cooler. In all cases we recommend 3.55 rear gears or steeper to maximize initial acceleration before the boost ramps up. Here's to another 20 years of centrifugual fun. Congratulations, Vortech, on the silver anniversary, and thanks for celebrating it in black!
Wheeling The WheelAlthough far from fully tuned, Vortech generously put us behind the wheel of its '11 test mule so we could begin our blown Coyote education.
Happily, we must say a '11 Mustang GT putting down 460 Clydesdale horsepower to the rear tires is a smoking good time. Switch off the traction control, put a couple of thousand rpm on the tach, trade clutch and throttle pedals with authority, and the big GT blazes the rear tires as much as you command. With the rear end slowly swinging side-to-side, First gear goes by quickly; an enthusiastic granny shift keeps the music squealing in Second. It takes a touch of driving to maintain directional control, and as speed builds to the top of Second gear and your tire-frying resolve begins to wane in favor of forward motion, the 5.0 will be ready to hook up. A speed shift into Third would no doubt bring a satisfying bark from the rear tires, but we didn't want to visit such aggression on Vortech's shiny red bit of test equipment, so we left that for you to explore. But it definitely has some steam.
In Second gear roll-ons, the blown GT not so much exploded but wound up in a hurry. With no boost gauge, we found it impossible to tell what rpm the blower was taking practical effect, though it's not for a lack of trying. Seat-of-the-Levi's, it's simply impossible to say where the revving Coyote starts gaining from the Vortech blower because the power ramps up smoothly. (The dyno shows extra power from lower than 2,000 rpm.) Experienced as we are with Vortechs-we believe we were the first magazine to sample the then-new centrifugal in 1990-it was no surprise to feel the GT pull harder and harder in a swelling rush as rpm built. This is the big cookie in centrifugal supercharging-the building power rush-and it's definitely there in the new GT.
With all that happiness duly noted, we must also say the '11 Mustang GT is a heavy beast, and to make it a snappy street performer requires more rear gearing than the common 3.31 cog. The 3.55s should be just right with the Vortech for all-around use, while the g-junkies and smoke-'em-if-you-got-'em crowd will no doubt find the 3.73s willing partners. The smooth, linear power of the Vortech should be real treat on a road course, too. There, the constant high-rpm tempo is well-matched to the centrifugals power output, good adiabatic efficiency, and minimal weight gain.
As a street piece, the subdued V-3 Vortech blower is well-mannered. It makes a light, high-pitched gear whine that's just audible at idle, at least with stock mufflers and the radio off in the quiet '11 cockpit. There is no scream or siren-calling under boost, but there is big industrial air noise from the bypass valve with each shift and when holding some engine speed, say 4,000 rpm, at part-throttle. That's from the large volume of air being bypassed, and Vortech notes it has a quieter bypass exit arrangement it could fit. We drove with the standard K&N-type cone filter on the bypass outlet, which in our old age we thought obtrusively loud. If you're wanting a hot-rod persona, the little filter is your buddy; if preserving the '11's decorum is a goal, go with the quiet bypass.
Of course, there's always something, and when we drove Vortech's test mule, the electric power steering was mysteriously inoperative. Luckily the EPAS uses a stiff T-bar (that's a small torsion bar previously used to tune hydraulic-assisted steering feel, but a simple mechanical link with EPAS), so without assist, the steering is merely high-effort and not the rubbery, non-linear mess of a non-op hydraulic system. In fact, it reminded us of when men were men and drove vehicles like our buddy's 427 Cobra.
On The DynoVortech uses its in-house Mustang Dyno for development, a test rig notorious for lower readings than the ever-popular Dynojet. In fact, while we often guestimate flywheel horsepower as 15-percent lower than that reported by a typical Dynojet, 24 percent is a more accurate multiplier with Vortech's Mustang Dyno. As it is, we saw 450 rwhp on Vortech's dyno during the run we're presenting here.
Note how the rpm, boost, and horsepower are linear. The torque wanders some, with the Coyote's characteristic dip around 4,000 rpm-it must be the variable cam timing causing this.
Vortech intelligently aims for a conservative tune, using 10.7:1 as the air/fuel ratio target and timing set for 91-octane fuel. This is necessary to cover the real-world variables, and lets East Coasters custom-tune an extra 30-40 hp with their readily available 93-or-better-octane pump premium.
We can also see how boost really doesn't get out of the 7-psi range on this development run. Vortech's goal is 8 pounds of boost and 500 rwhp using the off-road inlet pipe.
Of course, the racers are already far ahead of all this. Tuned into the low 11:1 air/fuel range, spinning the supercharger to 10 pounds with a T-Trim and the engine well into the 7,000-rpm zone, racers had already run an automatic '11 GT as quick as 10.73-second e.t.'s using East Coast premium pump gas at press time for this issue.