mufflers

I think an X-pipe w/ a flowthrough muffler is about the closest you're gonna get without swapping to one of those engines. Its not completely the exhaust system that gives those cars the sexy exhaust note.

If you wanna go extreme(without spending a ton for an exotic motor) to get that sound, your best bet will be a lexus V8.
http://www.youtube.com/watch?v=QtgoFrDGBFE&feature=related
but who wants to go through that much hassle for an engine that doesnt have a ton of aftermarket? and will have half the people on this site calling you unamarican(misspelled for annunciation purposes

Yes I know that the engine makes a lot of the difference on how it sounds.. But actually 318 and 360's are really close to the same bore stroke, and none of them are weird firing intervals, So once I change the cam and upgrade heads an such it shouldn't be out of the range of possibility to try for a sound like that. The Chevelle was close to what I am looking for.

And I don't think the lexus engine is what I am looking for. kinda small and anemic for my tastes! haha! thanks for the ideas though!