can i submit papers showing my new pay raise alongside my i864 showing i make enough to support three persons?

Having a job letter and recent payslip showing higher pay to support your husband and uncle are definitely not enough if this is a case for consular processing. If for adjustment of status, U.S.C.I.S. may send you a Request for Initial Evidence a few months after you submit the case for your husband's adjustment of status. The normal time for interview after filing with U.S.C.I.S. in most field offices is approximately a year. Assuming that you have submitted the next year's tax return at the higher rate of pay by the time of either receiving the Request for Initial Evidence or the date for interview, your financials might be good enough to convince an immigration officer of your ability to support at the interview. For safety's sake, however, you may wish to have a joint sponsor to avoid the possibility of denial. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.