Two Ferrari 458 Challenge prototypes spied on the Fiorano Circuit this week, and we have the photos. What's different? Find out inside.

Two different Ferrari 458 Challenge prototypes were spied for the first time during track testing earlier this week.  One of the prototypes was spotted on the Fiorano Circuit near Ferrari's Maranello, Italy, headquarters, wearing different front and rear bumpers than the 458 Italia.

Possibly for benchmarking puroses, we can see one prototype wearing the Challenge styled fascias in primer gray while the other prototype keeps the standard 458 bumper fascias.  The unfinished Challenge fascia is also wearing a bit of camouflage in the center setion of the bumper.  It also appears to carry different styling near the front wheels.  Hood pins were also installed on the test vehicles, which are riding on center-locking nine-spoke wheels.  The new rear bumper is relatively the same, saving for the dual exhaust pipes instead of three tailpipes on the 458 Italia.

A number of lightweight pieces were also installed, with changes to the seating and windows.  The test models are also using large brakes, a new roll cage, and a plastic driver's side window.

The Ferrari 458 Challenge will also use thinner body panels to bring weight well below the Italia's 1,380 kg (3,042 lbs).  It uses a 4.5-liter V8 engine that generates 562 hp (319 kW, 570 PS), and up to 540 Nm (398 ft-lb) of torque.  It will be mounted to a dual-clutch F1-style gearbox, with F1-Trac control, electronic differential, and a racing suspension also installed.