What is the difference between a 1 liter engine and 2 liter engine?

Answer 1

The two litre engine can theoretically "ingest' two litres of air and fuel mixture into its cylinders. The one litre engine will only be able to take in one litre. I say theoretically because there are many other things to consider when trying to fill the cylinders to maximium capacity. Intake manifold design, valve timing, number of valves per cylinder, intake port size, valve lift, duration and overlap to name a few. Most modern normally aspirated engines will be able to reach 70%-75% volumetric efficiency. Adding a turbocharger or supercharger could push the volumetric efficiency over 100% depending on boost levels.. You would be forcing more air into the engine than it could take in on its own. The more air and fuel you can squeeze into the cylinders, the more power the engine will produce.