A key design goal of the 1992 Turbo S was to increase the engine power over the standard 3.3 ltr turbo (M30/69 – 235 kW/320 bhp) and the X33 increased power option (M30/69S – 261 kW/355 bhp). The M30/69 SL Turbo S engine achieved this goal attaining 280 kW/381 bhp using a combination of different camshafts, precision-machined intake ducts, slightly higher charge pressure and an optimized ignition and fuel injection system. The result was a top speed of 290 km/h (standard – 270 km/h, X33 280 km/h) and 0 – 100 kph at 4.7 seconds.
The following information on the 911 3.3 Litre – Turbo S Leichtbau is from the factory technical bulletin ‘Xe’.
The upgrades from the M30/69 started with more aggressive camshafts, new injection valves and minimum boost pressure raised to .78 bar (from .75 bar on the M30.69 engine) using a standard K27 7200 turbocharger. Engine load was reduced by the omission of the power steering pump and A/C, polishing of the fan components, and the replacement of the dual engine driven fan and alternator and A/C belt system with a single belt with the engine cooling fan mounted directly to the alternator shaft. Finally a second oil cooler was mounted where the A/C condenser was normally found. The engine is instinctively recognizable by its trademark Guards Red air filter housing and intercooler shroud.