The "engine types" field is not for the engine code. It's just for the engine configuration, i.e. "I4" for inline four. Somebody either put "K20" in as a joke or as a mistake.
The configurations should be broken out more thoroughly. Especially not that turbocharging smaller displacement engines is being embraced by most manufacturers. There should be "I4" and "I4-forced induction"
Well, then we should talk about what engine types should be on the list. From what I gather, L should be changed to inline and H should be changed to "Flat". Nobody uses letters to describe those engines.