In order for the engine to work with the maximum possible return, it is necessary to increase its thermal efficiency to the maximum. To get the “ideal” engine, you need it to work without heat loss; in fact, this is not possible, but by bringing the efficiency closer to the maximum value, you can get a more powerful engine. During the combustion of fuel, heat is released, it expands the products of combustion in volume, which subsequently push the piston. But the heat is partially dissipated to the metal surfaces that are around. This leads to excessive heating of the engine and partial waste of fuel. Therefore, it is obvious that if you reduce the heat consumption for heating the engine and let it work on the piston, you can save a lot. There are several ways to improve thermal efficiency. Obviously, the first of them is to take less heat-conducting metals for the cylinder head, since this is where the main heat loss occurs. If you take aluminum heads (high thermal conductivity), the result will be a higher compression force and a decrease in sensitivity to detonation, aluminum also gets a greater gain when insulated with a thermal barrier, but the power will be noticeably reduced, since there will be heat loss in the water jacket. If you take cast iron (low thermal conductivity), then the result will change in the opposite direction, respectively, the power will increase. Note: Cast iron is great for low compression engines.You can find out how on the website: autocarinfo The second way to improve thermal efficiency is a new technology in the automotive industry: coating the metal with a thermal barrier, which will significantly reduce the thermal conductivity of the metal, and, as a result, heat loss. The use of this high-tech insulation material with a thickness of only 0.4 mm has become widespread among motorists. The increase in power rating after coating with insulation depends on three things: the size of the combustion chamber and the material and design of the head. The standard increase in engine power and fuel economy will be 3%. And the thermal efficiency will increase by values from 4 to 8%. The overall increase in power will be about 10%. Thus, protecting the engine from heat loss or partially, preventing it, you will significantly increase its performance and save on fuel.