John Roncallo owns a unique 1986 Mercedes 560SL (R107). The car originally came with a 5.5 L M117 V8 making 225 hp and four-speed automatic transmission. At some point the factory powertrain was swapped for one from a 1996 Mercedes SL600 (R129). This means in the engine bay is a 6.0 L M120 V12 making 389 hp and 421 lb-ft of torque. Behind the motor is a 722.6 five-speed automatic transmission and R129 rear differential. The car also received the wheels and front brakes from the SL600. You can read more about the project in the build thread.
What a beautifully done swap. I appreciate the preserving of the original look of the car, even with the newer wheels. I used to detail an old friend’s 560SL and thought the V-8 took up a lot of space in the engine bay. That V-12 fills it even more, but it looks great. The only bad thing about the car is that someone my height (6’6″) doesn’t fit in it very well.