Thanks for your reply Jarek.
I previously spent quite some time researching engine oils and its properties. Your data is for modern, synthetic oil, which didn't exist in the 1920s. So, I opted for four types of mineral oils for the Vega: SAE-10W, SAE-20W, SAE-30 and SAE-50. All calculations for viscosity, kinematic viscosity, density, etc. are already implemented, they just don't take much of an effect just yet (see pages 6+7 of the debug panel - shift+9). Interesting that the density of modern oils is so low. I'm dealing with mineral oil with a density of ~0.89kg/l
As you may know, I am currently working on the heat-exchange module. Each component of the engine is calculated separately, it has physical properties like mass, heat capacity, geometry, etc.etc. Then I create relationships between the components ad define them by the type of heat-exchange (i.e. conduction, convection, radiation). At present, this module contains around 30 different components and around 100 relationships.
I am now at the point of tuning the parameters, which is why I asked my questions above. I need to have a rough idea of how hot each component gets to compare my calculations.
Thanks for the paper you linked, it's very much relevant to this work!!