Maserati's upcoming 5-Series fighter will feature an oil-burner under the hood.

Fiat-owned Maserati is scheduled to launch a new sedan that will be smaller than the Quattroporte in 2013. It will compete in a lucrative market segment that has historically been dominated by the BMW 5-Series and the Mercedes-Benz E-Class.

Going head-to-head against the two German heavyweights is easier said than done. To make sure that the yet-unnamed sedan is up to the task, Maserati will reportedly fit it with a diesel engine, marking a first in the company's long history.

The engine in question will be a 3.0-liter V6 unit developed jointly by Italy's VM Motori and Fiat Powertrain Technologies. It is already found under the hood of the Chrysler-based Lancia Thema, but it will be heavily revamped before it is deemed worthy of sitting behind a trident-adorned grille. Sources say that the oil-burner will be fed with two turbos, giving it about 320 horsepower and over 500 lb-ft of torque. If these numbers prove to be correct, they would make the Maserati sedan more powerful overall than the E 350 CDI, and give it more torque than BMW's 535d.

In addition to the diesel engine, the midsize sedan is expected to feature a standard (revised) 3.0-liter version of Chrysler's 3.6-liter Pentastar V6. The gas engine would get Fiat's MultiAir variable valve timing, along with twin turbochargers and direct injection, good for around 400 horsepower. Expect the sedan to run from around $80,000 to about $100,000.

As previous reports from Leftlane have suggested, this diesel powerplant may also find its way under the hood of the upcoming Maserati Kubang SUV as well. This would improve economies of scale, improving profit margins for both vehicles.

The small Maserati is part of the company's ambitious expansion plan.

"We want to sell 54,000 cars in four years," a company spokesman told Germany's Auto Bild.

That's roughly nine times more cars than the Italian brand sold last year.