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Cosworth 2004 Ford Focus

Royalty Comes To Visit

Photography by E. John Thawley III

The Cosworth Focus feels more like a full-blown front-wheel-driving racecar than any other front-drive street car we've tested. It's not just the carbon seats, R-compound tires or guttural, attractive rawness, but the immediacy of every mechanical action and the organic reaction each requires. The car showcases the full gamut of newly developed Cosworth parts for the Focus, in addition to a slew of parts from suppliers to create a complete package as wild as the powerplant.

The multiplicity of aftermarket offerings for nearly every make and model car is the result of people convinced they can do better than both the original equipment manufacturer or any other aftermarket competitor. One of the reasons this magazine exists is because parts of varying degrees of quality, engineering and efficacy create a huge aftermarket. Cosworth is kind enough to remove the guesswork for Ford Focus fans by providing the very best of all three.

England-based Cosworth Engineering is largely the reason the term high performance has been associated with four-cylinder Ford engines for the last 46 years. Meanwhile, they've won a few F1 championships. And WRC and Touring Car titles. And IndyCar and Champ Car championships. No entity is better qualified to lay hands on the Duratec powerplant.

The 2.3-liter PZEV engine is impressive stock, managing both decent power and torque production from a unit that produces less harmful emissions than most other gasoline engines on the market (PZEV stands for Partial Zero Emissions Vehicle).

Small ports and lots of intake and exhaust restriction leave little headroom for power growth, however, and are part of the reason torque falls after 4200 rpm and horsepower after 5800 on the stock engine. The result of fairly orthodox engine modifications by Cosworth, apart from a 65-percent increase in horsepower, is an engine transformed in character.

The Cosworth-modified PZEV dyno plot looks like it was made with a ruler, a meaty tableau of torque intersected by a wrinkle-free ramp of power that stops rising only 400 rpm before the fuel cut.

Cosworth offers three engine packages, with stages one to three offering a claimed 174-, 203- and 240-crank hp, respectively. The orange Focus in these pages has the contents of the catalog poured into it. Call it stage three.

The CNC-ported head features reshaped combustion chambers and enlarged ports that improve flow with the higher lift and duration cams. Stiffer valve springs allow the engine to spin another 1000 rpm, to 7700. According to Cosworth, much of the power was gained by using the "Power by Cosworth" cast manifold, a gorgeous piece that features both larger runners and a plenum with greater displacement with velocity stacks fitted to each runner. Attached to the manifold is a 67mm throttle body mated to a Cosworth intake and air cleaner.

Tuned for California's impotent 91-octane fuel, the Focus laid down 199 hp at 7400 rpm and 148 lb-ft of torque at 6300 rpm, although nearly as much torque was being made as early as 3500 rpm. A clutch problem during our test prevented the car from shifting properly at high rpm, saddling it with a 14.9-second quarter mile at 96 mph. Had it engaged correctly, a few tenths could likely be lopped off that time.

We're used to normally aspirated four-bangers that make this much power having the emblem "VTEC" stamped somewhere on them. Unlike those engines, however, this one makes power and torque below 5000 rpm, so while you're still rewarded for revving the piss out of it, there's no penalty if you don't.

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