An engine is at the heart of every Porsche, so Porsche Classic Motor Oil was developed in collaboration with Porsche Development in Weissach and Porsche Classic experts. It was designed with the aim of meeting the demands of the 356 and 911 models including 993s and was extensively tested in laboratories and in practical trials where its operating behaviour and lubricating properties were put to the test. The engine oil also had to meet other demands because not every classic Porsche is in everyday use classic vehicles are often left stationary for long periods of time and only moved intermittently and for short journeys, which means that condensation can form in the oil if the engine does not heat up fully.
Aggressive combustion residues can cause acidification of the oil fill, resulting in the corrosion of engine components. The alloys, metals and sealing materials which were used at the time are at particular risk. Porsche therefore paid particular attention to this aspect when developing its Porsche Classic Motoroil. The special formulation incorporates a high alkaline reserve, which neutralises any acids that may form. Additional corrosion inhibitors also protect vulnerable components, even during longer stationary periods. Every Porsche, and air-cooled flat engines place particular demands on a lubricant. The thermal load is higher than in water-cooled units, for example, which means that the engine oil has to work harder to cool the engine down. The larger oil volume firstly entails a longer oil heating time, and secondly calls for optimum cold running behaviour. The traditionally high power output per litre of the engines also results in high compression and high pressures. Together with the different temperature zones which are characteristic of air-cooled engines, this means that the oil needs a high "hidden" performance reserve.
A compact and lightweight engine design means that the connecting rods will be short in relation to the piston stroke, which in turn means high lateral piston forces and correspondingly high demands on the lubricating film stability of the oil. In short, the older flat engines in particular can't just use any old oil. The development of an engine oil for classic air-cooled flat engines has therefore been something akin to a balancing act between tradition and innovation: as advanced as possible and as traditional as necessary.
20W-50 for the 356, 914 and early 911 models
10W-60 for the 911 from a displacement of 3.0 litres