By Kurt Ernst

So far, McLaren has been tight-lipped about the potential output of its new P1 supercar. Until now, all we’ve known for certain is that it will benefit from a supplemental Kinetic Energy Recovery System (KERS), meant to boost horsepower under acceleration. Technically, speaking, that makes the P1 a hybrid automobile, though that’s where the similarities between it and a Prius end.

McLaren’s P1 supercar – image: McLaren

The P1’s twin-turbo 3.8-liter V-8 (borrowed from the McLaren MP4-12C) will make 727 horsepower on its own, with peak torque (531 pound-feet) available from 4,000 rpm. Boosting output is a McLaren Electronics-designed electric motor, rated at an additional 176 horsepower and 192 pound-feet of torque. Since electric motors make peak torque from 0 rpm, that’s power that can be used to get the P1 moving, quickly, from a standstill, and if you’re keeping score at home that produces a total output of 903 horsepower and 723 pound-feet of torque.

McLaren’s P1 supercar – image: McLaren

Feeding the electric motor is a high-density battery pack that adds just 211 pounds to the car’s weight. To ensure maximum efficiency and cell life, the pack is liquid cooled, and it can be completely recharged (with a supplied plug-in charger) in only two hours. Once full, the pack supplies enough power in full electric mode for up to 10 kilometers (6.2 miles) of driving.

McLaren’s P1 supercar – image: McLaren

The real purpose of the hybrid system, however, is supplemental power. There’s an IPAS (Instant Power Assist System) button on the steering wheel, and pressing it instantly serves up the extra 176 horsepower and 192 pound-feet of torque the electric motor delivers. KERS isn’t the only Formula One technology employed by the P1, either; opposite the IPAS button on the P1’s steering wheel is a button labeled DRS, for Drag Reduction System.

McLaren’s P1 supercar – image: McLaren

Like an F1 car, the P1 uses a movable rear wing to adjust downforce. While downforce adds grip in a corner, it also takes away speed in a straight line. Thumbing the DRS button will change the rear wing’s angle of attack, decreasing drag by as much as 23-percent. Release the button, or hit the brakes, and the rear wing takes a steeper angle, increasing drag and rear downforce.

Look for further details on the McLaren P1 to be revealed when the car breaks cover at the upcoming Geneva Motor Show.

…read more
Source: FULL ARTICLE at Automotive Addicts