If you maintain residency in the USA you are also maintaining residency in a state. If that state charges income tax, you need to add that to your liability to compare with the taxes you'd be paying in Italy. Added to that, you need to maintain healthcare while in Italy. Additionally, if you stay in Italy one day longer than half a year, you become a tax resident in Italy.
You ask a highly fact sensitive question, Depends on what your tax status will be under the Italy/US Tax treaty., residency requirements of the state in the US, etc.. https://www.irs.gov/businesses/international-businesses/italy-tax-treaty-documents . The 183 day rule will apply to "residency" but not necessarily to tax residency. A competent international tax attorney is a must before you make a decision.