i have a new intake (low restricted one) with 8.5mm wires and new plugs. i am currently seeing what a 2" exhaust with a twin loop muffler is going to cost. Are headers worth the trouble since i live in PA, i have to relocate the cat? And do the UR pulleys decrease engine life by alot like i heard?Advance the spark carefully, and listen for pinging or knocking. Those WILL hurt your engine, and performance too. Go for the easy things first. A KN air filter (or any low restriction filter), a cold air intake, new spark plugs (along with a complete tune up of course). Maybe a lower restriction muffler. If you want more fun, a little razzy sound will make the car feel like it's doing more.
All these mods can happen one at a time, fairly cheaply, and will make small increments of difference in performance.