From Wiki:
"The E55 AMG is powered by the M113 ML55 engine, a 5.4 L V8 with a Lysholm type supercharger manufactured by IHI. The E55's engine was rated at 476 PS (350 kW; 469 hp) and 700 N·m (520 lb·ft), the low end of the supercharged 55 range due to its longer exhaust system, compared to the SL55 AMG's engine at the high end which made 517 PS (380 kW; 510 hp) and 720 N·m (530 lb·ft).[14][15] The reality however was that the E55 was actually tuned to 493hp from the factory just as the S55 AMG. Mercedes' 469 hp number was part of the marketing strategy to differentiate the more expensive S55 AMG. Only the SL55 has more power due to a larger throttle body. The supercharged 5.4 L V8 engine was mated to the Speedshift 5-speed automatic transmission, which has a torque capacity of 796 lb·ft (1,079 N·m)*, as the newer 7G-Tronic introduced in 2003 is limited to 542 lb·ft (735 N·m), not enough to handle the torque from the supercharged V8.[16][17]"
*fingers crossed..
