BMW and Mercedes-Benz make different cars for different people. There’s a lot of overlap though, and we’re not just talking about both German automakers building great straight-six engines decades ago and now. While Mercedes has always seemed to lean a bit more towards luxury, and BMW a bit more towards providing a great driving experience, both have created some truly iconic cars over the years. Thirty years ago, BMW was building the E34 M5, which used an outgrowth of the M88 inline-six of the M1 (more on that later), and Mercedes—with the help of Porsche—was making the 500E. The 500E was built atop the Mercedes W124 E-Class platform, and this is where we begin with this interesting one off, the 1988 Harte F1.
Originally a 1988 Mercedes-Benz 300E with 188 horsepower from stock, while the specific history of the car isn’t known, at some point, it was given a heart translate by the BMW-tuner Hartge brothers. The original Mercedes M103 SOHC 3.0-liter six was removed, and in its place went a BMW M88, the 3.5-liter twin-cam, 24-valve six originally of the M1, which was also used in the E28 M5 (excluding the U.S.) and the M635CSi. Although Mercedes is known for its smooth and durable automatic transmissions, the high-revving personality of the M88 on display below has been preserved in this W124 chassis by way of a five-speed manual transmission from an E24 6 Series.
The modifications did not stop at the drivetrain transplant, however. The M88 engine itself was bored out from the factory 3,453cc displacement to 3,535, and the suspension of car was replaced with a performance-oriented setup using Bilstein dampers. Output is claimed to be 330 horsepower—more than the 500E of the 1990s—but torque may be another story. Nonetheless, performance was described as, “shocking,” in its day, and the Hartge F1 was reportedly built without regard for cost.
Aside from a cursory summary that mentions what’s broken down above, the car is described as unrestored with no odometer reading listed. Magazines containing articles about the car when it was freshly built are said to be included, but other important details, like its history, remain unknown. Nonetheless, it appears to have been subject to a full Hartge build with parts like the steering wheel, shifter, and wheels, and we’re inclined to believe the, “only example of its kind” descriptor.
If you’re really curious about this BMW-Mercedes Hybrid though, you always just make it your own, because it’s scheduled to be auctioned this summer in Essen, Germany by RM Sotheby’s.—Alex Tock
[Photos courtesy RM Sotheby’s.]