Year: 1974 | Generation: Carrera RS | Units built: 109 RS 3.0s, 54 RS trim
Engine: Flat-6 | Power: 230 bhp | 0 – 60 mph: 5.2s | Top Speed: 155 mph
During a successful 1973, Porsche took the opportunity to develop an evolution of the RS 2.7 (having now met stricter requirements of building 1000 road cars per year in line with Group 3 rules). A quirk in the Group 3 rules allowed previously homologated cars (like the RS 2.7), to be homologated with just 100 examples built. So, in 1974, Porsche launched the Carrera RS 3.0. It was almost twice as expensive as the 2.7 RS but was much more of a track machine. The chassis was similar to the ’73 Carrera RSR and the brake system was from the Porsche 917. It was a continuation of the race cars for the road trend that all of us Porsche fans love so much.
The 3.0 made 230hp with what was basically as detuned 3.0-liter RSR engine with an aluminum (rather than magnesium) crankcase and street exhaust fitted in place of the open racing unit. Cylinder heads were single-plug rather than the racing twin-plug type, and the compression ratio was given a significant bump over the outgoing 2.7’s 8.5:1 ratio, though it still runs on the equivalent of 93 octane U.S. pump gas.
With its systematic lightweight construction, the RS 3.0 only weighed in at 900 kg. This low weight was achieved by using thin-gauge sheet parts and by basically removing parts and equipment from all over the place. Brakes were upgraded to larger four-piston units and the suspension was revised with RSR rear pick-up points allowing for more camber adjustment. There was a five-speed gearbox and limited-slip differential, and the fenders were widened even further to accommodate 8.0-inch wheels up front and 9.0-inches in the rear. The RS 3.0 also had the taller, larger bumpers introduced in all 1974 911s and the new rear “tray”-style spoiler.
Before you ask we love both the RS 2.7 and RS 3.0 the same. The 2.7 is the ultimate dual-purpose 911 from the era. Somebody once nailed it when they said: “The RS 2.7 is 80 percent 911 S. The RS 3.0 is 80 percent RSR.”