Cavalier Performance

I just bought a 2003 Cavalier 2 dr. 5spd. I absolutely love it and I was strongly considering doing some performance mods in the near future. I looked around on the internet and decided to install headers, a cat-back exhaust system and an air intake...by having all these mods, approximately how much more horsepower/torque will i gain? The 2.2 ecotec is rated at 140hp/150lbs-ft of torque (for those of you that dont know and I am sure most of you do).
Also, are there any specific headers, cat back systems, CAI's that will outperform competitors or are all of them pretty much the same and the name is all u pay for? Please share your wisdom with me. Thank u.

for intake I'd chose RK Sports polished WAI, catback I'd go with 2.25 inch piping to a magnaflow or dynomax muffler and as far as a header goes I'd get the Weapon R, seems thats the only header that doesnt have clearence issues. You will probably pick up 10 to 12 whp with these 3 mods if you're lucky.

dont waste your money on bolt ons. You can gain at very most 15-20 HP and spend well over a grand on the car. Or you can save your money for a few months and wait for the GM supercharger to come out. Im saving up for the GM SC for my cavy, with my 2.4L SC it will have 190HP.

Hey thanks for your help guys...Good advice.. I have thought about a supercharger believe me. I figure I am going to spend about $1000 at least for catback,headers and CAI so why not save my $ and get an SC. Good point, but is it not true that if I drop a supercharger I will have to tune my engine so that it can handle it?

with the GM SC its designed for that engine and that engine only. And when you put it is installed, GM flashes your ECU so that its tuned for you. ALso the GM SC if they install it comes with a 12 month 12,000 mile warranty and does not void your current warranty like any other SC would.

GM doesn't have a supercharger out yet for the Ecotec...

GM doesn't have a supercharger out yet for the Ecotec...No shit, That's why -Jayson- said if he WAITED a few month's he could get the supercharger..