What is the difference between turbos and gas compressors in cars?

Answer 1

a turbo recycles unburnt gases,(fuel)back to be used and burnt. a gas compressor compresses fuel before it enters combustion chamber to make engine, more efficient

1. The above is wrong and not even worth remembering.

A turbo does not recycle exhaust gas back into the intake stream, that is the job of an EGR (exhaust gas return) valve. A turbocharger works by using the expansion factor of a super heated gas passing from a compressed state to a non compressed state to rotate a turbine wheel on the turbine side of the turbocharger. This is the side that all of the exhaust gasses will go through once expelled by the engine. The exhaust gasses are then routed to the tail pipe via the exhaust system. The turbine wheel is attached to the compressor wheel by the turbo shaft. The compressor wheel draws filtered air from the air filter and compresses it. In a gas engine you must understand that the engine has what is called a mechanical compression ratio often noted like 9.5 to 1. In a turbocharged or supercharged gas engine you must combine the mechanical compression ratio and the % factor of the turbocharger or supercharger to get a configured compression ratio. A higher compression ratio in a gasoline will increase power output. In a diesel engine a turbo performs the same way but is used to match fuel to air more than to raise the compression ratios which are usually about 20 to 1 and can be higher. I believe that the term "gas compressor" is sometimes used to explain a turbocharger in the European market such as the Mercedes Kompressor. Many of my European friends refer to turbocharged cars as gas compressor engines. To the above author who wrote that the gas compressor compresses fuel; you need to understand Physics. You can't compress fluid. Fluids are pressurized by a restriction in the fluid stream, if there is no restriction, there is no pressurization. The gasoline is supplied in volume by the fuel pump and restricted to a point by the fuel pressure regulator which bypasses any amount of overpressure back to the fuel tank. Now to the EGR valve. This valve takes an amount of burnt or inert exhaust gas and introduces it back into the intake stream. This gas is inert (there are no fuel calories left in this gas to burn) and is used to lower combustion temperatures. Oxides of nitrogen (represented as NoX) are created at combustion temps of 2500 degrees F. and over. By introducing an inert gas (approx. 10%) there is less air and fuel by volume and therefore lower combustion temps.