Isdera Imperator 108i - GT body - manufactured in 1988
No, I'm not mistaken. This truly isn't a Mercedes though it definitely looks like something Mercedes could have made and bears the famous Mercedes star. It's is manufactured by ISDERA, an acronym for "Ingenieurgesellschaft für Styling, Design, und Racing" (engineering company for styling, design and racing), from Leonberg near Stuttgart in Germany and originally sported an impressive chrome falcon on its front grill. The car was the brainchild of engineer Eberhard Schulz and even if it's not directly linked to Mercedes there are some strong connections.
Eberhard Schulz started his career in the automotive industry in rather an unusual way; largely self educated he constructed in 1968 a sportscar named the Erator GTE. It was an attractive twoseater with gullwing doors inspired by the Ford GT40 and powered by a 1600 cc VW engine in the rear. Porsche engineers were quite impressed it with and it landed him an engineering job in the bodywork department at Porsche. Around the same time Mercedes presented its first C111 prototype: a distinctly wedge-shaped sportscar in striking orange functioning as a testbed for rotary and later diesel engines. The C111 was developed up to 1979 in various versions but from the beginning Mercedes had made it clear that it would not lead to a production model. Some people were disappointed by that and felt that the C111 could have been a worthy successor to the iconic 300 SL sportscar from the 1950s. One of those people was Eberhard Schulz. Next to his day job at Porsche he started to design a car that should be good enough to be the new 300 SL in his spare time.
From 1972 to 1978 Schulz worked on the car that was dubbed CW 311, indicating its (low) drag coefficient (Cw 0,311) as well as referring to the C111. He incorporated elements that recalled the 300 SL, most notably its gullwing doors, but for the most part the design was firmly rooted in the supercar era of the time. Developed as a mid engined sportscar it slotted right in with the Lamborghini Countach, Maserati Bora, Ferrari BB512 and ultimately the BMW M1. Its heart was a 6.8 litre Mercedes V8 engine developing 375 hp. When it was finally unveiled in 1978 it was proudly fitted with Mercedes emblems and presented as a Mercedes prototype. The small detail that the Mercedes company hadn't been consulted about this or wasn't involved any official way was easily neglected in all the turmoil that followed.
Apparently it appeared at the right time because it generated a lot of publicity. With a top speed of 319 kph, aggressively attractive looks and unique features like its periscope rear mirror on the roof over the drivers seat, its hideaway headlights and of course the upward opening doors it instantly became every boys dreamcar. What was equally unique was that Mercedes wasn't annoyed by Schulz's audacity but rather embraced the car. This more or less proved that Schulz had achieved what he had set out to do: constructing a performance car in the right Mercedes idiom. The CW 311 was promoted by Rainer Buchman of the then fashionable B & B tuning company and appeared in magazines and publications world wide and even in a German motion picture.
The CW 311 was in reality a rather brutal car and not really suited for every day use. In total 3 were made and one now resides in the Mercedes factory museum. It did however establish the name and qualities of Eberhard Schulz and by 1983 he left Porsche and started for him self with Isdera. The first car to be introduced by his new company was the Spyder 033i, a car rather looking like a smaller and roofless CW 311 and powered by 4-cylinder VW and later 6-cylinder Mercedes engines. It was nimble and quick but because of the lack of windshield and roof more of what we now call a trackdays car. Only 17 were made up to the end in 1993.
Isdera's most important car arrived in 1984 and was named the Imperator 108i. In effect it was the CW 311 turned into a production car. While retaining the looks of the CW 311 it featured numerous improvements making it a much better car. Most notable differences were the longer wheelbase (+8 cm) and the new front design with recessed headlights with transparent covers, a louvered bonnet and the Isdera falcon in front instead of the Mercedes star. Still, customers could order the Mercedes emblems if they wanted for the first series of cars and maybe that's what happened with the car shown here. The car itself was a tubular frame construction with a fibreglass body glued on to it. Longitudinal behind the seats a V8 Mercedes engine was placed, coupled to a ZF 5-speed gearbox. Standard the engine displaced 5 litres and produced 235 hp which was enough for 265 kph but more powerful versions were offered as an option: a 5.6 litre V8 with 300 hp and 282 kph and two AMG tuned 32 valve versions with up to 420 hp and 308 kph, turning the Imperator into a true supercar.
In 1991 the first series Imperator was concluded with an EVO 1 version, a car built to FIA GT specifications and meant to be a racecar. It was wider and lower and featured updated bodywork. The 5 litre engine was modified extensively and produced 330 hp making it the fastest Imperator up to then at a top speed of 310 kph. Unfortunately the car never raced and was sold as a street legal vehicle. Total production of the first series Imperator amounted to 17 cars with most of them being exported.
After the EVO 1 followed the series 2 Imperator which featured revisions to almost 60% of the components. Externally the three vents above the front wheels and return of the hideaway headlights made it easy to distinguish. But it still looked a lot like the original CW 311 shown more than a decade before. The car was made safer and more civilized; an exhaust catalyst was introduced as well as anti lock brakes. Newly designed Mercedes engines were fitted which now had exhausts at the sides of the car, just before the rear wheels, instead of in the rear. Two versions were offered: a 5 litre version with 330 hp and 300 kph and a 6 litre version with 410 hp and 320 kph. In 1993 another revision followed which largely consisted of better brakes and larger wheels. Around 13 series 2 Imperators were made though officially production of this model has never ended.
The pinnacle of the Isdera model line up was introduced in 1993 after 6 years of development as the Commendatore 112i. It was a completely new design that took cues from Group C racing cars and had a very low drag coefficient of Cw 0,300. With a sleek low shape and a remarkably large rear deck it was a striking car. Like the previous Isderas it featured a mid engine lay-out and this time a Mercedes V12 engine was fitted, cranking out up to 620 hp and promising top speeds around 370 kph. Unfortunately it came at a time when the market for supercars was in decline and soon after Isdera had to file for bankruptcy. The company was acquired by Swiss investors but since then activities have been fairly limited and mainly focussed at engineering work for outside contractors. Unclear is how many Commendatore models have been made; according to some there is only the prototype from 1993; other sources mention also a Commendatore made in 1999.
A last appearance (up to now) by Isdera was made in 2006 when the unusual prototype Autobahnkurier 116i was shown. It was a retro-styled (indicating streamlined design from around 1936) and featured two V8 engines placed behind each other in front under a very long bonnet, making it a 16 cylinder car. It was nothing like the other Isdera models and remains a single prototype.
Though it was an initiative of an individual the remarkable CW 311 prototype has taken its place in Mercedes history. In a way it filled the gap between the classic 300 SL and the current SLS AMG and has accumulated almost as much credibility which is no mean feat. It launched the enigmatic Isdera cars that virtually without any promotion or advertising became known around the world. And still after so many years the deriving Imperator seems fresh and exciting. Those are the makings of a true classic, even if the name doesn't ring a bell and production didn't amount to more than a few handfuls.
© André Ritzinger, Amsterdam, Holland