[Ridenour]

welcome to the forum mike.

Aftermarket exhaust is a great mod for your grand am. There are all sorts of factors that come into play in getting the right exhaust note - everything from tip size / angle, to muffler type. Backpressure will not be an issue with your exhaust, unless you were to do something drastic, such as cutting it off at the engine block. The flows and pressures in any standard aftermarket exhaust should run fine with your engine. There's a couple routes you could take to have a new exhaust installed. You could find one (such as a nice cat-back system) online, and install it yourself, or you could buy it and have a shop put it in, or you could just have a shop do a custom job. You would also need to pick the right muffler that you liked the sound of (magnaflow, flowmaster, turbo, ect.) and have it installed, and pick a set of tips that would sound good (upper angled = higher pitch, lower angled = more rumbling) - or if you have just a cat-back system installed, it may make it sound decent enough that you won't want a new muffler. The possibilites / combinatiions are endless. Good luck.