The V-8-engined 5-series gets a power boost of 35 hp and 30 lb-ft of torque for 2006 thanks to the newly modified 4.8-liter V-8 engine that recently debuted in the face-lifted 750i. That 4.8-liter mill is a bored, stroked, and tweaked version of the 4.4 liter from the 545i model. Apparently BMW would rather have vehicle names divisible by five nowadays than monikers that reveal an engine's exact displacement as they did in years past. Regardless, the more powerful engine helps move the 750i along that much more quickly, and it should silkily do the same with the 550i.