As does its Zetec cousin,...
As does its Zetec cousin, the PowerWorks SVT-specific blower looks more like an intake manifold than a power-adder from the top, making it stealthy to casual underhood observers. Then again, there aren't many knowledgeable Focus types who don't know full well what that PowerWorks lettering means. This supercharger/manifold/intercooler assembly is just one preassembled part of this power-packed $4,975 kit.
Focus Fact: PowerWorks' former parent company, Cosworth Technology-previously owned by Audi-has been gobbled up by another German giant, Mahle. PowerWorks is now a division of Mahle Powertrain.
Last year (Spring '05, p. 30), we laid out the impressive credentials of PowerWorks' first Focus offering: an intercooled Roots-style supercharger kit engineered specifically for the five-speed 2.0 Zetec. Said kit quickly earned our Two-Fanatical-Thumbs-Up award for its Mr. Hyde performance and Dr. Jekyll driveability. Since then, we've anxiously awaited release of the promised SVT Focus version of the kit, and the wait is finally over.
Engineering the SVT-specific kit required a fair number of changes from the base Zetec package. Some of those modifications, such as the increase from the Zetec kit's 36-lb/hr fuel injectors to the SVT's 42-lb/hr units, will be specific to the SVT version. But others, such as a relocated vacuum tree assembly on the blower air inlet neck and a totally repositioned remote oil filter, will from now on be common with a second-generation version of the Zetec kit. The SVT's six-speed Getrag gearbox-more specifically, its shifter-cable routing-also caused some kit additions and revisions. Other challenges in the SVT project included the tuning calibration peculiarities of its variable cam timing-a calibration that, in order to achieve CARB exemption, was programmed with emissions legality as a primary consideration (see Tuning for Boost sidebar).
This is the view your firewall...
This is the view your firewall will see. As evidenced by the drive pulley and inlet routing, the PowerWorks casting architecture puts the M62 blower on the bottom of the assembly, discharging upward through a hidden intercooler into the manifold/plenum chamber. This shot also shows the all-important bypass valve, with a shield plate on the SVT version owing to the proximity of the Getrag tranny's shift cables. The four-port vacuum tree is now higher on the inlet than it was on the Zetec kit we showed you in the Spring '05 issue. This is now the standard vacuum tree position for all SVT and Zetec kits.
What hasn't changed for the SVT kit is the M62 (62 ci of air per blower revolution) Eaton/MagnaCharger positive-displacement supercharger, with 2.8-inch pulley. Installed on a Zetec, this setup can generate as much as 13 pounds of boost pressure, but this drops to around 10 psi on the SVT Focus, thanks to its less restrictive cylinder head and exhaust header. If that concept gives you pause, just think of trying to blow an identical volume of air through a drinking straw (the Zetec) and a radiator hose (the SVT). Clearly, the lower-restriction passage will generate less pressure-pressure being nothing more than a measurement of resistance to flow. In any event, this drop in boost works out nicely since there's no way the SVT's higher static compression ratio (10.2:1 versus 9.6:1 for the Zetec) could have endured 13 psi of boost without drastic retardation of spark timing to lower peak cylinder pressures-something that would have more than cancelled any benefit from higher boost.
Like its Zetec counterpart, the PowerWorks SVT kit is intercooled. To be more specific, the hot breath of the supercharger gives up much of its BTUs to coolant circulating through an effective air-to-liquid heat-exchanger element located within the intake-manifold casting. At the other end of this liquid circuit, the coolant-constantly circulated by electric pump-is in turn chilled by air cascading through a much larger under-bumper-mounted heat exchanger. For those just tuning in, the benefit of intercooling is that the lower the air temp in the cylinders, the more spark advance they can take without risk of detonation, and greater spark advance generally equates to more power and efficiency, all else being equal. For these reasons, it's hard to find factory forced-induction applications without intercooling. On the other side of the ledger board, intercooling dictates a higher kit cost and a somewhat more complicated installation process.
Speaking of installation, bolting on the SVT kit is similar to-though a bit more complex than-the Zetec install we showed you previously. Feel free to refer back to it for more detail. PowerWorks' installation manual is outstanding, so what we'll mostly concentrate on in our captions is how the SVT kit differs from the Zetec's.
Was PowerWorks' SVT blower kit worth the wait? Well, let's see: Does 233 hp feel better than 150? Our official thumbs are pointing skyward again.
 Because the SVT Focus has...  Because the SVT Focus has no EGR valve, the inlet casting comes with a block-off plate (yellow arrow) installed. The red arrow is pointing to one other minor, but important, revision in the SVT kit's manifold casting: a small area machined to clear the SVT fuel rail. The blue caps in this shot are installed for shipping, and seal off the intercooler coolant passages. |  The main difference between...  The main difference between the SVT (right) and Zetec manifold castings is the intake port size and shape. This dramatically larger port area is one reason the identical blower and pulley arrangement produces about 3 psi less boost on the better-breathing SVT. But trust us: The eager SVT doesn't need as much boost as the Zetec. |  The SVT kit uses the same...  The SVT kit uses the same molded air-inlet assembly (and 65mm BBK throttle body not shown here) as the Zetec kit, but substitutes 42-lb/hr injectors, whereas the Zetec kit gets by with 36-lb/hr squirters. PowerWorks also sticks with the stock SVT spark-plug heat range, but calls for gapping them down to 0.045 inch to ensure boost doesn't blow out the spark. Failure to close the gap results in the spark giving out just above 5,000 rpm-we know because we tried it. |
 SVT kit hardware also includes...  SVT kit hardware also includes a new shift-cable bracket (top right) to keep the cables out of the blower's way, along with a specific lower rear-mounting bracket for the blower. The oil-filter relocation bracket on the left is also new, but is now common with the second-generation Zetec kits. It places the filter in the driver-side wheelwell instead of the passenger-side subframe rail location used on the early Zetec kits. |  As in the Zetec kit, PowerWorks'...  As in the Zetec kit, PowerWorks' SVT kit includes clearly labeled plug-and-play harnesses wherever electrical connections are necessary. Not a single wire need be cut or spliced during installation-a point of great relief for the majority of us with a primal fear of the incomprehensible world of electrons, and handy if your SVT should ever need to be returned to stock. |  As with the Zetec kit, the...  As with the Zetec kit, the PowerWorks SVT kit completely dispenses with the factory airbox and snorkels. The battery's removal, on the other hand, is only temporary to provide working room to eventually mount the intercooler pump. |