Well, I got a Hypertech Max Energy for my Jeep Wrangler. It worked great. It only took me like 5 minutes to tune. Look into a Airaid cold air intake (I think it's better than K&N) and look into a Flowmaster exhaust. Use good spark plugs and run Lucas fuel treatment and upper cylinder lube in it.
hypertech is great. Reasearch at summit racing. Cold air intake, chip, and definately exhaust (headers, and back...) They make a swell supercharger setup for the 5.3 as well, depending on how much you want to spend
