Which countries do not require visas for Brazilian travelers ?
- If exist what is the maximum number of days of stay in country?
Wikipedia actually has up-to-date pages that answer this question with colour-coded maps and tables, for every citizenship of the world. All the information is backed by official references.
The page for Brazilian citizens is Visa requirements for Brazilian citizens.
The Mercosul countries do not require passport, only RG (Identity card) with a recent photo.
Note: Usually the maximum period is 90 days.
Source in portuguese: Correio Brasiliense