Both clubs are in Group A with four-time champions Esperance of Tunisia and Nouadhibou from Mauritania.
Wiliete shocked defending champions Mamelodi Sundowns of South Africa in the final qualifying round last weekend, drawing 1-1 in Pretoria to win on away goals.
The Angolans are captained by Mabululu, the leading scorer in the premier African club competition this season with four goals.
Petro staged a dramatic comeback to edge Scottland of Zimbabwe. Trailing 2-0 after the first leg, they won the return match 3-0.
It was the first game of a second stint at Petro for Portuguese coach Alexandre Santos. He was in charge of beaten finalists FAR Rabat of Morocco last season.
Former champions Orlando Pirates carry the hopes of South Africa. They are in Group C with Renaissance Berkane of Morocco, Simba of Tanzania and Colombe of Cameroon.
Bubista, the coach behind the fairytale progress of Cape Verde to the 2026 World Cup knockout stage, is now in charge of three-time CAF Confederation Cup winners Berkane.
Simba are coached by South African Steve Barker, who faced Pirates many times before moving to East Africa. The Tanzanian club were among four who won all four qualifying matches.
Pyramids of Egypt, winners of the Champions League two seasons ago, are coached by Rulani Mokwena, another South African.
He boasts a perfect record this season with four victories in Africa and seven in the Egypt Premier League.
Pyramids are in Group D with Al Hilal of Sudan, Horoya of Guinea and Maghreb Fes, winners of the Moroccan championship last season for the first time in 41 years.
Zamalek of Egypt have been African champions five times, but not since edging Raja Casablanca of Morocco in 2002.
Their Group B rivals include Young Africans of Tanzania, who sacked South African coach Manqoba Mngqithi after qualifying. The club said players "did not understand his tactics."
CAF Champions League groups:
Group A: Esperance (TUN), Petro Luanda (ANG), Nouadhibou (MTN), Wiliete (ANG)
Group B: Zamalek (EGY), Young Africans (TAN), Mouloudia Alger (ALG), Club Africain (TUN)
Group C: Renaissance Berkane (MAR), Simba (TAN), Orlando Pirates (RSA), Colombe (CMR)
Group D: Pyramids (EGY), Al Hilal (SUD), Horoya (GUI), Maghreb Fes (MAR)