Hi there!
About the Endurance Brasil series, I can help you guys with some information, but since there is a lot to cover I started a dedicated thread to the series.
As was already posted, the championship has 8 classes, evenly split between prototypes and GTs/Touring Cars, however the regulations on the site have been updated during 2019, and are available at the CBA site:
https://www.cba.org.br/campeonato/downloads/86/416/2019
The classes are as follows:
P1: Brazilian built prototypes + LMP3 cars + Ginetta G57 P2. Engines are limited to 7.000 cm³ NA or 4.200 cm³ turbo/supercharger.
P2: Brazilian built prototypes of older build, with the same engine specifications as P1, but different weight and fuel capacity limits. The car Tarso Marques built was intended for P2, however as it is a new design it's going to be competing at P1.
P3: Prototyes with engines up to 2.400 cm³ NA engines.
P4: Prototypes with engines up to 2.100 cm³ NA engines, with a mandatory low cost Pirelli tyre. For 2020 this class will be merged with P3 due to a lack of interest in the last years
GT3: GT3 Homologated cars. Until 2019 the GT3 cars were limited only by weight/fuel cell capacity, however seems 2020 onwards the FIA BoP will be mandatory
GT3 Light: older GT3 cars + Brazilian Stock Cars
GT4: FIA GT4 cars with FIA intake restrictors + a few locally prepared GTs / Touring Cars.
GT4 Light: FIA TCR, GT3 cars built prior to 2008 and GTs/Touring Cars from various one make series from Brazil, lite the Trofeo Linea, Maserati Trofeo, Mercedes CLA AMG Cup, among others