I have a 05 automatic S40 2.4i completely stock except for a cold air intake. Im trying to make it sound better..Eventually gonna get an exhaust but for now should i take off the muffler and put a resonator on? Anyone know where i can find one?

 

Your exhaust should have a muffler and a resonator already in place.
First I'd cut out the center resonator and see how that sounds. Then if need be, replace your current muffler with a flowmaster muffler. I've heard them on a few 2.4i's and they sounded really good.
Any exhaust shop can do the resonator delete for you.