Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
ahead [əˈhɛd] adv впереди́; (direction) вперёд
ahead of (more advanced than) впереди́ +gen (earlier than) ра́ньше +gen
ahead of time or schedule досро́чно
go right or straight ahead иди́те вперёд or пря́мо
go ahead! (giving permission) дава́йте!
they were (right) ahead of us они́ бы́ли (пря́мо) пе́ред на́ми
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.