Porsche has unveiled its 2017-spec 919 Hybrid, which is set to debut in next month's FIA World Endurance Championship season-opening Six Hours of Silverstone.
Like the new Toyota TS050 Hybrid, also revealed Friday at Monza, the updated German LMP1 challenger is an evolutionary step from last year's car, having retained the same 2.0-liter V4 engine and battery-based hybrid systems.
However, optimizations have been made in nearly all areas, including the two energy recovery systems, a KERS-style unit mounted on the front axle and exhaust recovery system on the rear, which both feed an updated lithium-ion battery.
The biggest change has been made in the aerodynamics, with the FIA and ACO's new safety-related changes aimed to reduce cornering speeds and, as a result, aero efficiency and downforce.
It's resulted in a significantly different look at the nose and sidepods.
So what's new?
According to team principal Andreas Seidl, who also remains as the technical director, 60-70 percent of the car is newly developed.
"The basic concept of the 919 Hybrid still offers scope to optimize the finer details and further boost efficiency," Seidl said.
"The monocoque is unchanged since 2016, but the optimization potential of all other components was analyzed and, in most cases, adjustments made accordingly."
Seidl confirmed that the car unveiled Friday features Porsche's low-downforce Le Mans aero kit, while it is yet to confirm when it will debut its high-downforce configuration.
LMP1 rules see a reduction from three to a maximum permitted two aero kits per season.
Despite the new developments, Seidl said the 2017-spec car has not exceeded the weight of last year's car, thanks for further optimizations.
Porsche will field two 919 Hybrids in the entire nine-round WEC season, with defending World Champion Neel Jani being joined by Audi LMP1 refugee Andre Lotterer and Nick Tandy in the No. 1 car.
Tandy's 2015 Le Mans-winning co-driver, Earl Bamber joins the No. 2 lineup alongside the returning Timo Bernhard and Brendon Hartley.