I don't think you can make an EDH deck just with those 2 sets, but what you can do and it is the better option is to build just the core of your deck with those 2 sets and build the rest with cards from any set, what I mean is: don't restrict yourself to just those 2 sets for the card draw, mana ramp, target and mass removal. Once you have about 10 mana ramp, 10 card draw, 5 targeted removal and 5 mass removal, you only need around 30 cards for your deck.