1991 Isdera Imperator 108i

History has revealed endless amounts of vision, desire, and creativity, and in the automotive realm, designers, engineers, and businessmen have focused these gifts on realizing their automotive dreams, but only a few successfully. While some measure success by completing the project, others have loftier goals of financially rewarding their time and efforts. Then, some visionaries skip to the 'head of the line,' bypass the stages of experimentation, testing, and failed projects, and introduce a ground-breaking automobile that is instantly a Paragon of performance and style. Such is the story of Isdera and its Imperator 108i.

Isdera (Ingenieurbüro für Styling, Design und Racing)

German-born Eberhard Schulz was in college when he built his first car in his garage in 1969. It was based on a Volkswagen Type 3, had a mid-mounted engine, and was called the Erator GTE. Upon completion, he drove it to Porsche's and Mercedes-Benz's headquarters in hopes of securing a job, using the car as his resume. Impressed, Porsche gave him a job in their design department. After eight years, Schultz left Porsche and joined the b&b company, founded by Rainer Buchmann, where he would go on to design the Mercedes-Benz CW311 concept. It was designed, built, and promoted by b&b and - with approval from the manufacturer - wore Mercedes-Benz badging. The mid-engine concept was powered by a Mercedes-Benz V8 engine, had a spaceframe chassis, gull-wing doors, and was intended as a spiritual successor to the legendary 300 SL of the 1950s. When the project was declined by Mercedes-Benz, Schulz established his own engineering company to produce the car under his own brand, Isdera.

The Isdera Imperator 108i
What had been called the CW311 became the Imperator 108i, and a production-ready version was completed by 1982. While it retained many of the styling features of the original show car, the overall design had been refined and perfected for the road. It continued to use the exotic gull-wing doors and periscope rearview mirror, but the pop-up headlights were replaced with two fixed units, and more conventional tail lights sourced from Mercedes-Benz.

The Imperator 108i received a tubular steel spaceframe chassis with a 98-inch wheelbase, an overall length of 166 inches, a width of 72 inches, and a height of just 45 inches. The body was formed from fiberglass in coupe configuration with seating for two. The front was suspended via double wishbones, while the rear employed a multi-link setup similar to the one used on the Porsche 928.

Initially, power was courtesy of a 5.0 liter Mercedes-Benz M117 V8 engine mounted mid-ship and powering the rear wheels. As time progressed and Mercedes-Benz developed more potent V8 engines, the Imperator 108i became a recipient. Later engines included an enlarged version of the Mercedes-Benz M117 V8 with a 5.6-liter displacement size, a 5.6-liter AMG V8, and a 6.0-liter AMG V8. These engines were paired with a five-speed ZF manual transmission, and the two AMG engines featured 32-valve cylinder heads.

The 5.6-liter M117 V8 was sourced from the SL 560, had single-overhead camshafts, and delivered approximately 300 horsepower. The original Imperator 108i with the 5.0-liter engine had a zero-to-sixty mph time of around 5 seconds and a top speed of 283 km/h. The AMG version had double-overhead camshafts and delivered upwards of 390 horsepower.

Production began in the early 1980s, with the first customer taking delivery around 1983 or 1984. Each car was built to order, and (initially) no more than two cars were built yearly. The exotic styling, blistering performance, and exclusivity were expensive and with a price that far exceeded most other automobiles.

After seventeen examples had been built, the Imperator received styling revisions, which bestowed a more curvy and modern design, a redesigned front grille, optional wing mirrors and the re-introduction of pop-up headlights. Additional vents were positioned in the front near the doors, and the previous three vents were replaced by NACA ducts.

Beginning around 1991, thirteen examples were built with the updated design when production ceased in 1993.

by Daniel Vaughan | Oct 2023