best oil for Audi How to renovate a historic car?
Antique cars are of real interest among car lovers. Very often they are looking for a model produced in a particular time and acquire such a copy is just the beginning. Buying historic cars usually require a thorough overhaul. However, such action made sense, it is worth spending some time to find true professionals, who not only undertake such a difficult task, but also will be able to restore such vehicle to its former glory. New paint, repair any plumbing and of course a major service mechanisms and systems inside the car requires a lot of time, and sometimes money, but the end result is worth such a sacrifice.
Rare visits to the sites of car
As you know, most of the people going to the car service decides to take this step due to the sudden emergency situation and still persisting problems with the car. Of course, there are also compulsory inspection of cars, but apart from a cursory check the performance of our car hardly anyone decides on a thorough diagnosis of the car. This is primarily associated with costs that have to be incurred in connection with the sometimes very costly repairs and replacements of car parts. Often the repair turns out to be also unprofitable, because it exceeds the value of the car. In such cases, the best solution would be to sell the car.
Another manipulated property
Most motor oils are made from a heavier, thicker petroleum hydrocarbon base stock derived from crude oil, with additives to improve certain properties. The bulk of a typical motor oil consists of hydrocarbons with between 18 and 34 carbon atoms per molecule.7 One of the most important properties of motor oil in maintaining a lubricating film between moving parts is its viscosity. The viscosity of a liquid can be thought of as its "thickness" or a measure of its resistance to flow. The viscosity must be high enough to maintain a lubricating film, but low enough that the oil can flow around the engine parts under all conditions. The viscosity index is a measure of how much the oil's viscosity changes as temperature changes. A higher viscosity index indicates the viscosity changes less with temperature than a lower viscosity index.
Motor oil must be able to flow adequately at the lowest temperature it is expected to experience in order to minimize metal to metal contact between moving parts upon starting up the engine. The pour point defined first this property of motor oil, as defined by ASTM D97 as "... an index of the lowest temperature of its utility ..." for a given application,8 but the "cold cranking simulator" (CCS, see ASTM D5293-08) and "Mini-Rotary Viscometer" (MRV, see ASTM D3829-02(2007), ASTM D4684-08) are today the properties required in motor oil specs and define the SAE classifications.
Oil is largely composed of hydrocarbons which can burn if ignited. Still another important property of motor oil is its flash point, the lowest temperature at which the oil gives off vapors which can ignite. It is dangerous for the oil in a motor to ignite and burn, so a high flash point is desirable. At a petroleum refinery, fractional distillation separates a motor oil fraction from other crude oil fractions, removing the more volatile components, and therefore increasing the oil's flash point (reducing its tendency to burn).
Another manipulated property of motor oil is its Total base number (TBN), which is a measurement of the reserve alkalinity of an oil, meaning its ability to neutralize acids. The resulting quantity is determined as mg KOH/ (gram of lubricant). Analogously, Total acid number (TAN) is the measure of a lubricant's acidity. Other tests include zinc, phosphorus, or sulfur content, and testing for excessive foaming.
The NOACK volatility (ASTM D-5800) Test determines the physical evaporation loss of lubricants in high temperature service. A maximum of 14% evaporation loss is allowable to meet API SL and ILSAC GF-3 specifications. Some automotive OEM oil specifications require lower than 10%.
Źródło: https://en.wikipedia.org/wiki/Motor_oil