For nearly 50 years, Porsche has managed to continuously develop the 911 to keep its position as one of the world's great driving machines. No one can argue that the current 997 models are the best 911s ever.
There are, however, a strong body of Porsche enthusiasts who maintain that the switch from air-cooled to liquid-cooled engines in 1998 when the 996 debuted robbed the 911 of a unique part of its appeal. Porsche had no choice, as it had reached the limit of managing engine heat while striving to meet increasing demands for more performance along with stricter noise and emissions regulations.
Porsche is to be credited for making the "new" 911s look and feel like their air-cooled predecessors, but nothing can replicate their unique mechanical resonance — the raspy exhaust note and the metallic symphony of whirring fan blades and clattering timing chains. And, of course, the soulful shriek that started at 5,000 rpm and continued through the 7,200-redline of the early 911S motors.
That noise, in concert with the rear weight bias, steering feedback and, yeah, the constant threat of oversteer made driving an air-cooled 911 like nothing else on the road. An experience not easily forgotten and one that, like the 911 itself, endures. Consider that prices for used 993 models, the last air-cooled models, remain substantially higher than those of the more powerful, more modern 996 models that succeeded them. Those who know Porsches, know which ones are worth paying extra for.
1963-'73: Lightweight, 2.0- to 2.4-liter engines, edgy handling
1974-'77: Transitional period for the U.S., when bumper laws affected styling and emissions cut power
1978-'83: 911SC returned some of the lost performance and updated styling
1984-'89: Carrera 3.2: more power, better handling, other improvements
1990-'94: Type 964: controversial styling; first all-wheel drive cars; not quite ready for prime-time electronics
1995-'98: 993: return to traditional styling cues, more performance, improved reliability over 964, beloved as last of the air-cooled 911s