Ahli, who had their initial request to postpone the game until August 9 rejected by the Confederation of African Football (CAF), had hoped to play the match in Cairo with a 2200 local time start as their players are fasting during Ramadan.
However, officials have banned all sport in the country's major cities because of security fears.
Sunday's match will now kick off at 1630 local time in El Gouna, 430 kms from the capital and the venue that was used for Ahli's opening group match against bitter rivals Zamalek that finished 1-1 last week.
The Pirates had asked for the match to be moved to a neutral venue because of concerns about travelling to Egypt but CAF rejected that.
Since the military toppled former Egyptian president Mohamed Mursi in early July, nearly 300 people have been killed in violence, including 80 of his supporters gunned down at dawn last Saturday.
(Reporting by Nick Said in Cape Town; editing by Clare Fallon)
