We drove the McLaren W1 in Ferrari’s front yard. Editor-in-chief Dan Pund spent some time out in Italy to test out the W1 at Mugello Circuit, Ferrari's backyard test grounds. Yes, that W1—McLaren's direct competitor to the recently launched 1184-hp hybrid Ferrari F80. It was surely no small thing for McLaren Automotive to make this car happen in the financial rough waters that makers of supercars ­frequently navigate. The W1 has a unique new carbon-­fiber monocoque. It’s the first model to carry McLaren’s all-new V-8 (the MHP-8, for those keeping track). It’s the only current McLaren to use a full race-style inboard front suspension, with 3-D-printed front control arms and a stunningly effective lowered Race mode. It carries an ironing board off the back of the car that, on its complex and beautifully rendered linkage, can extend nearly a foot rearward and flip up when needed—the term “active aero” barely does justice to its balletic moves. That wing, the big underbody diffuser, an...