What are the limitations for the 1st stage liquid fueled rocket engines that are currently in widespread use, what are the factors that limit their total thrust? Why can't you just inject more and more fuel in the same sized engine to produce more thrust for example??
By limitations, I mean the largest factors that stop these engines from producing more thrust. I would assume that it's something like the heating of the engine, or the rate at which the fuel can be burnt / passed through into the combustion chamber.
Could you also explain how these factors limit the thrust produced?