Back in 1988, German tuning house Hartge built the F1 using the chassis of a W124 Mercedes 300E and the M88 3.0-liter straight-six from a BMW M1 and E28-generation BMW M5 shoehorned under the hood. It’s the equivalent of giving a Mercedes-AMG E63 an M5 engine and getting away with it. While Hartge was known for squeezing bigger BMW engines into smaller chassis all the time, the F1 was a little more experimental, with cross-swaps between BMW and Mercedes an uncommon notion back in the late 80s.
But the tuner believed the W124’s chassis was capable of handling far more power than the 187 horsepower it received from the factory, with the M88 providing it with 325 hp and 258 lb-ft of torque – albeit through a series of modifications. To achieve the outputs, the engine was bored from 3,452 cc to 3,535 cc, and the engine was paired to a manual gearbox from an E24-generation 6 Series to direct power to the rear axle. Bilstein sports suspension was the final topping on the F1, turning it into a gloriously capable performance sedan.