The McLaren Senna, aka the P15, has finally arrived and it comes to the party toting a 4.0-liter V-8 that delivers 789 horsepower and 590 pound-feet of torque – the most powerful engine that McLaren has stuffed in a road-going supercar so far. But, it’s not just the power that makes this thing downright potent. See, the Senna is also the lightest road-going car built by McLaren to date (with the exception of the legendary F1,) tipping the scales at just 1,198 kg or 2,641 pounds – that’s less than the minimum curb weight for the 2017 Honda Civic, 2017 Subaru BRZ, and the BMW 3 Series. And, it’s no more than 300 pounds heavier than the 2017 Mazda MX-5 Miata. Sure, they are in a different class, but that’s the point. All told the car is so light that it has a power-to-weight ratio of 658 horsepower per ton – a staggering figure to say the least. Those are just the basics, though, so keep reading to learn more!