BIRMINGHAM, U.K. - Jaguar could have saved time, effort and cash if its design team had gone retro in the first place in shaping the S-Type "Junior Jag" unveiled here at the British International Motor Show.

However, it took five iterations - not many as clay-model exercises go - to get precisely what Jaguar wanted: A smaller, sportier car to appeal to a younger, less-affluent clientele, yet unmistakably a Jag.

In the end the much-anticipated new model - only the third since Jaguar was acquired nine years ago by Ford Motor Co.- borrows classic cues from the vintage 1960s Mark II and original S-Type, leaving no doubt about its pedigree.

With its small chromed grille and round, side-by-side running and fog lamps, the S-Type especially evokes its antecedents up front. In back, the taillight layout is mindful of its bigger sister, the XJ series sedan.

The S-Type represents a $750-million investment by Ford. It moves into production next month at the revamped and expanded Castle Bromwith facilities in this central England city and goes on sale in March. It's expected to carry a sticker in the mid-$40,000 range and compete against the BMW AG 5 series, Mercedes-Benz C-Class and Lexus GS 300/400.

Design work began early in 1995 under Jaguar Styling Director Geoff Lawson. "We recognized we had to keep the Jaguar heritage, but we hadn't done a sporty saloon (sedan) since the Mark II more than 30 years ago," he recalls.

Retaining Jaguar's distinctly British character was especially crucial, because the S-Type was developed under - and shares the platform of - Ford's rear-drive DEW98 program, which includes the Lincoln LS models arriving next summer.

The S-Type's 240-hp 3L DOHC V-6 uses the basic block and camshaft from Ford's 3L Duratec V-6, although engineered and outfitted to meet Jaguar specifications.

Jaguar's own 4L, 281-hp DOHC V-8, some of whose technology is applied to the V-6, is optional. The V-6 hits 60 mph (97 km/h) in 6.8 seconds with a top speed of 146 mph (235 km/h). The V-8 cuts that to 6.6 seconds and tops out at 150 mph (241 km/h).

A 5-speed manual gearbox is standard with the V-6 and a new 5-speed electronically controlled automatic transmission is available with both engines.

The last thing Ford or Jaguar wanted was speculation that the S-Type would be tagged as a toothless cat, given its co-development with the Lincoln LS. To avoid that, besides unique styling the S-Type has a distinctly Jaguar ride and handling characteristics and a long list of advanced features. "What Ford has done is make this car possible," says Michael Dale, president of Jaguar Cars of North America.

Side air bags are standard, while a "Dynamic Stability Control" system links antilock brakes with traction and steering.

Jaguar claims an industry first with an optional ($1,100) voice-actuated system that controls the audio, phone and climate control system using simple voice commands. There's also onboard satellite navigation.

S-Type production capacity initially is 50,000 annually. Its official forecast: 85,000 in 1999 and 90,000 in 2000.

Approximately half of S-Type sales are targeted for the U.S. Mr. Dale forecasts 30,000-plus U.S. sales in 1999, including 18,000 S-Types, and 24,000 S-Type sales in 2000 with full-year availability. Jaguar's best-ever year in the U.S. was 24,464 in 1986.