Yahoo Autos The Mercedes 500E Is the Greatest Benz Porsche Ever Built
History is written by the victors; so are most autobahn stories. Yet, my abiding memory of Mercedes’s epoch-defining sport sedan came as an onlooker rather than a driver. A couple of years back, I was driving on an unlimited stretch of the A5 autobahn south of Frankfurt late on a summer evening. I’d rented a base Volkswagen Polo, which was incapable of any high-speed adventure itself. But I had a great view as fast movers streaked past.
Almost all of them were expensive late-model cars. But one wasn’t. A glance in the Polo’s rearview mirror delivered the unexpected sight of older halogen headlights closing at a significant pace. Seconds later, a W124-generation 500E streaked past at a speed that sent the Polo rocking in its wake, the Merc either close to or hard against its 155-mph limiter. It was a 30-year-old performance car still being driven as its creators intended.
Many cities are riven by deep rivalries, and although Stuttgart doesn’t have a sporting enmity to match that between the Mets and the Yankees, it does possess two automotive home teams, Mercedes and Porsche. These days, employee numbers and even sales volumes have grown closer, but back in the late Eighties, Mercedes was big and successful, and Porsche was small and struggling. The situation led to the joint parentage of the Mercedes 500E.
The 500E is all Mercedes. Every component carries one of the company’s parts numbers. But Porsche was contracted to engineer and build it. These days, both companies are equally proud of it; the car photographed for this story belongs to the Porsche Museum.
The W124 E-class launched for 1986 to critical and sales success but without any performance variant. Mercedes had already found success for a turned-up version of the smaller 190E with a Cosworth-designed 16-valve engine, so trying something similar for the E-class made sense, especially as future subsidiary AMG was already creating an aftermarket V-8 version. “BMW was in the market with the M5, and AMG had the Hammer,” remembers Jürgen Berghus, a young engineer at Mercedes in 1988, now 65 years old and recently retired. “So we decided to try to implement a V-8 engine.”
Before that, there was brief consideration of using a twin-turbo six-cylinder, but a prototype engine proved unsuitable. “The biturbo was very digital,” Berghus says. “It was one or zero, all or nothing.” Instead, the E-class would get the contemporary 500SL’s 5.0-liter M119 32-valve V-8, which could be squeezed into the W124’s engine bay with slight surgery. Mercedes had built prototypes, but it lacked the resources to make a production version, with its engineers flat out on the 1990 R129 SL roadster and 1992 W140 S-class.
Enter Porsche. The sports-car maker’s contract-engineering division was one of the few parts of the business that was still doing well. “It was a time of crisis at Porsche,” says Michael Hölscher, now 68 and retired, one of the company’s engineers for hire at the time. “The production numbers in Zuffenhausen had decreased from 80,000 to 18,000, so it was very good news that Mercedes gave us this job. It was not the only component in Porsche staying alive, but it was a very good brick in the wall.” Hölscher had just finished a GM project and went to work on the 500E. Mercedes had set all the core targets. Berghus shows an internal document from 1987 that stipulated a 250-km/h (155-mph) top speed, the figure that BMW and Mercedes had agreed to limit their most powerful cars to.
While the regular W124 E-class was a spectacular piece of engineering and is widely regarded as one of the pinnacles of Mercedes quality—even now, some still work as taxis in parts of the world—it was no sport sedan. Mercedes designed it for comfort and refinement. As launched, the most powerful version had 177 hp. The new car would need more than 300 hp to deliver on the performance targets.
The Porsche Museum’s 500E becomes a demonstration tool at this point, with Berghus and Hölscher happy to school me on the many differences between it and the regular E-class. One of the cleverest is effectively invisible, with the need to feed cold air to the engine stymied by the requirement for much larger radiators that would entirely fill the space behind the grille. Instead, the design team took advantage of the high-pressure area at the front of the car and created ducting behind the headlights, with more than enough air flowing through the gaps around the lights to feed the engine. Peaks of 322 hp and 354 lb-ft might look slight by modern standards, but they were enough to make the 500E one of the fastest sedans in the world, even though the four-speed automatic gearbox (chosen because the company’s five-speed unit couldn’t handle the torque) meant the engine would be running close to max revs at top speed.
There are numerous other chances to geek out over details. The 500E has double reinforcement struts between the front upper crossmember and the front crash bar (the regular W124 E-class has one), ordered after the test team discovered slight hood vibration while going flat out.
With the car raised on a ramp in the museum workshop, there’s also the chance to see the strengthening brace between the two front suspension arm mountings and the relocated steering rack. The larger rear differential also required a raised rear floor—the reason the 500 is a four-seater and couldn’t be ordered with a bench in the back. It got a bigger 23.8-gallon fuel tank to give realistic autobahn range.
