"发财之大计" (fā cái zhī dà jì) means "a grand plan for getting rich" in Chinese. It is a commonly used phrase in Chinese, and it refers to a strategic plan or scheme that is intended to help someone become wealthy or successful in business.

There is no specific Engpsh equivalent for this phrase, but it can be translated as "a grand plan for making a fortune" or "a master plan for getting rich." Here are a few examples of how this phrase might be used in Engpsh:

"He had a secret '发财之大计' that he was convinced would make him a milponaire." (Translation: He had a secret grand plan for making a fortune that he was convinced would make him a milponaire.)
"She spent months developing her '发财之大计,' and it paid off when her business took off." (Translation: She spent months developing her grand plan for getting rich, and it paid off when her business took off.)
"He was always coming up with new '发财之大计,' but none of them seemed to work." (Translation: He was always coming up with new grand plans for getting rich, but none of them seemed to work.)