" It's hard to believe it has been over a decade since Mercedes strapped turbos to its SOHC V12 creating the insanity that is the M275 engine. The idea seemed crazy at the time as the 5.5 liter M275 available in 600 models put out 493 horsepower and an earth moving 590 lb-ft. Mercedes AMG decided to give the entire automotive industry a huge middle finger and show who the king of power output truly was by taking that same motor and increasing displacement to 6.0 liters with more aggressive tuning and boost for 604 horsepower and 738 lb-ft of torque.
It was so much power and torque back in 2004 many wondered if AMG had gone too far. The cars featuring the engine (the S65, SL65, and CL65 AMG) were absurdly expensive. The other absurd part about these cars was their depreciation. The CL65 AMG depending on options was a $180,000+ car back then. Today, you can pick up a nice used example in the $30k range. The car was not an investment that is for sure.
What does this money get you? A twin turbo V12 luxury rocket with 528 horsepower and 674 lb-ft of torque to the wheels. A simple ECU tune will bring those numbers up into the low 600's to the wheels for horsepower and close to 800 lb-ft of torque at the wheels. A quality tune will run you a little over a grand.