Few model names carry as much weight as the Porsche 911 S. The 1967 and 1991 iterations represent different chapters in this storied nameplate's history, each reflecting the priorities and technologies of its era. The 1991 Porsche 911 964 Turbo holds a clear advantage in raw power with 320 hp compared to 160 hp, a 160-horsepower difference that shapes the driving experience. Under the hood, the contrast is notable: the Porsche 911 S uses a Flat-6 SOHC 12V displacing 1,991 cc, while the Porsche 911 relies on a Flat-6 Turbocharged with 3,299 cc. In the sprint to 60 mph, the 1991 Porsche 911 964 Turbo edges ahead at 4.8 seconds versus 7.6 seconds. The Porsche 911 S carries a weight advantage, tipping the scales 970 lbs lighter. Both trade at comparable values on the collector market, making the choice between them largely one of personal preference.