The C8 Spyder is the original base model with an Audi 4.2 litre V8 engine giving the car 400 PS (290 kW) and a top speed of 300 km/h (186 mph). The C8 spyder T has a more powerful Audi 4.2 litre V8 twin turbo with 525 PS (386 kW) giving it a top speed of 320 km/h (199 mph). The C8 Laviolette has the 400 PS (290 kW) Audi engine but unlike the spyder models that come with a fixed roof with a glass canopy. The C8 Double 12R is a version made specifically for the 24 hours of Le Mans also using the Audi V8 engine with 480 PS (353 kW) and the C8 Double 12S is the street version of this car which has the same glass canopy of the Laviolette and optionally has a 620 PS (460 kW) engine instead of the 400 PS (290 kW) engine from the C8 spyder, giving it a top speed between 301 km/h (187 mph) and 345 km/h (214 mph) depending on the engine. Both Double 12 versions have a modified C8 spyder frame with a longer wheelbase and a bigger fuel tank, Info from Spyker Wikipedia.