On this episode of Head 2 Head Jonny Lieberman is joined by Mike Shaffer and two extremely potent hyper sedans, the 2014 BMW M5 Competition and the 2014 Mercedes-Benz E63 AMG S Model. Between the two of them, these two mighty Germans produce 1152horsepower and 1092 pound-feet of torque. On paper. After a day of horsing around/testing Shaffer and Lieberman grow suspicious of each twin-turbo V-8's actual output. So, they take them to the dyno gurus at K&N engineering to learn what's