Does ARAM give the same amount of XP ( Or similar ) to Summoners Rift?

not 100% sure but based on average game time alone, its less becuase aram games are shorter.

I still feel that the "per minute" xp is lower in arams, but at the same time, aram pre game lobbies shave minutes from every game.

Supposedly yes in terms of raw game-time. Queue time, champ select, and such would bias XP gain though.