The Audi S8 is already a formidable beast, what with its 520 twin-turbocharged horses thundering_forth from_its 4.0-liter V-8. But the mad scientists at German tuning shop MTM are never satisfied. Hence the roadgoing rocket you see here: a beefed-up and boosted S8 that punishes the pavement_with a full 750 horsepower and nearly 700 lb-ft of […]