Audi's mid-engine sports car, the R8, is available in both coupe and convertible (Spyder) forms. Power is provided to all four wheels by either a 4.2l V8 engine or 5.2L V10 engine. The quattro AWD system has a strong 85% rear-wheel torque bias, but can send as much as 30% to the front wheels to improve traction. Standard equipment includes 19-inch alloy wheels, adjustable magnetic ride suspension, LED headlights and a Bang & Olufsen sound system. The R8 offers wheel, leather and carbon fiber packages to allow owners to customize their R8.