Once upon a time, when the German car companies had only just begun one-upping each other with continually increasing horsepower numbers, Audi's 80/90-series was the 97-pound weakling of the small-sedan crowd. Its buffest competitors, the 158-hp Mercedes-Benz 190E 2.6 and the 168-hp BMW 325i, boasted in-line sixes that made mincemeat of even the most powerful Audi 90 -- that is, until 1990, when the Audi 90 Quattro 20V showed up to challenge the big boys.
Ten extra valves pumped up the power output from 130 to 164 hp, dropping the four-ringed contender right into the thick of the fight -- and the 20V had something its rivals didn't: four valves per cylinder and a tachometer that didn't turn red until after it reached 7000 rpm.
Of course, the Benz and Bimmer engine blocks had one thing the Audi was missing: a sixth cylinder. Thumping under the hood of the 90 was a five-cylinder -- the divisive engine layout that seems to incite either love or disgust among critics. Some deride it as a lose/lose proposition that offers neither the smoothness of an in-line six nor the fuel economy of a four-cylinder. Others, upon hearing its gnarly, haunting exhaust note, are helplessly transported to a rally stage where a Group B Audi Quattro might pass a throng of frenzied spectators, creating thick clouds of dust as it claws for traction in full opposite lock.
European bureau chief Georg Kacher clearly wasn't feeling the rally-legend Michèle Mouton vibe when, in his October 1988 review of the Audi 90 Quattro 20V, he posed the question, "After all their diligent work, might the folks in Ingolstadt have better spent their time developing a smooth, torquey, potent in-line six?"
Well, if they had, their work would have been in vain, because a look under the hood of an Audi 90 confirms that a six would never have fit. As it was, the five-cylinder engine was practically wedged between the firewall and the grille. Space was so tight that there wasn't even room for a radiator up front -- it had to be located to the side of the engine. Besides, everybody loves a good six, but a great five would play directly into the hearts of Audi's rally fans.