Street-legal track cars don't get much better than the BAC Mono R. The standard BAC Mono was already certifiably bonkers, but the hardcore R version is even faster and lighter, with a 2.5-liter, four-cylinder engine producing 340 hp.
With a curb weight of just 1,223 pounds, the Mono R is 55 pounds lighter than the standard car, resulting in a power to weight ratio of 612-hp-per-ton and a 0-60 mph time of just 2.5 seconds. Impressively, this setup enabled the BAC Mono R to smash the production car lap record at the demanding Red Bull Ring in Austria during the Pirelli P Zero Experience.