How can I make my car sound good?

Get a SS induction kit and a K and N filter then look into headers hi flow cat and a sports muffler. I believe pacemakers specialize in commodores. Try the first 2 things 1st they will already change the sound a bit. Plus the CAI you can do yourself in 30mins or less. Headers/extractors help extract exhaust gases giving the engine better giving allowing it to make more HP or adding HP. Its just most factory exhaust systems are restrictive. Excluding the Honda Type R's which come with a pretty good setup changing it is just a waste of $$ not much gain or any at all.