The phrase "engines war" can be interpreted in a number of ways, depending on the context. If referring to a literal war involving engines (such as in the case of military vehicles or aircraft), then synonyms could include "engine conflict," "mechanized warfare," or "motorized aggression." In a more metaphorical sense, "engines war" might refer to a competition or struggle between different engines or technologies - in which case other potential synonyms might include "tech battle," "machine rivalry," or "innovation war." Ultimately, the most appropriate synonym for "engines war" will depend on the specific context in which the phrase is used.