Ford's 90-degree, overhead-cam Modular V8 has covered a wide spectrum since it was introduced in 1991--powering luxury cars, SUVs, pickups and high-performance sports cars.

A large number of those engines have come from a Ford plant in Romeo, Mich., which has now built its 10-millionth engine--a 4.6-liter V8 that is headed for a 2010 Mustang GT.

The Romeo engine plant was converted from a tractor factory. In 1991, it launched with a single-overhead cam, two-valves-per-cylinder version of the 4.6-liter Mod V8 for the 1991 Lincoln Town Car, rated at 190 hp and 260 lb-ft of torque.

Today it cranks out two-valve and three-valve versions of the 4.6-liter V8, with output ranging between 225 hp and 292 hp. The plant will build a three-valve 4.6-liter V8 for the 2010 Ford Mustang that will be rated at 315 hp and 325 lb-ft of torque.

Those engines roll down Romeo's high-volume production line, which stretches more than 4,000 feet. The plant turns out about 140 engines per hour.

Romeo also has a niche production line, where over the years workers have hand-built some of Ford's most-potent engines.

Today, the niche line builds the 540-hp supercharged 5.4-liter V8 for the Shelby GT500 version of the Mustang. Earlier, it built a similar engine for the Ford GT sports car, as well as V8s used in cars and trucks engineered by Ford's SVT unit.

In addition to assembling the engines, the Romeo plant produces many of the main components--iron and aluminum engine blocks, cylinder heads, crankshafts, camshafts and connecting rods.

During portions of its history, the modular V8 has been marketed as the Triton in Ford's pickups, and InTech in Lincoln vehicles.

While the Modular family shares a number of basic dimensions and design elements, the term modular originally referred to the highly flexible assembly line created to build the engine--which lets Ford quickly switch among different versions of the engine. The Modular family encompasses 4.6- and 5.4-liter V8s in two-, three- and four-valve configurations, and a 6.8-liter V10 that's been used in heavy-duty versions of Ford's full-size van and F-series pickup and in the now discontinued Excursion SUV.

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