Portland is 5 hours behind Rio de Janeiro
Best overlap: 1:00 PM to 6:00 PM in Rio de Janeiro is 8:00 AM to 1:00 PM in Portland.
Book within 1:00 PM to 6:00 PM Rio de Janeiro time (8:00 AM to 1:00 PM in Portland) and both teams will be at work. Portland is 5 hours behind Rio de Janeiro, so the practical overlap is about 5 hours — generous enough for meetings, tight enough to be worth booking ahead. For part of the year the maths changes: Portland observes daylight saving, Rio de Janeiro does not, shifting the overlap by an hour.