I meant the phrase "crate engine", not the existence of engines :) We generally call self-build cars "kit cars", because they come as a kit that includes every

I meant the phrase "crate engine", not the existence of engines :) We generally call self-build cars "kit cars", because they come as a kit that includes everything you need. AFAIK we don't have a specific word/phrase to specifically describe the engine (other than "engine", obv :)