From the Fiat 500 Abarth and Smart ForTwo to the Lamborghini Gallardo and Ferrari 599 GTO, no project is too big or too small for Romeo Ferraris. The Italian tuning house's latest project sits somewhere in the middle with a BMW M5. The result of their efforts is a pair of engine tuning packages for the 4.4-liter twin-turbo V8. The more powerful of the two packs an extra 97 horsepower and 81 lb-ft of torque for final figures of 657 hp and 583 lb-ft, while the less potent ECU tune releases an additional 75hp and 65lb-ft of torque.

The difference between the two comes down to the titanium exhaust system, including a downpipe with pre-catalyst, a catalyst metal center with 200 cells and titanium tips. Interested parties are urged to contact the tuning firm directly for availability and pricing, not to mention to exercise a measure of restraint when unleashing a car with nearly 660 horsepower on an unsuspecting world.