I just got a 2005 Cobalt SS/SC. I am getting an enlistment bonus in the next couple months and I am planning on getting the following mods, will I need anything else to make this work, and how much power can I expect from this setup.

XTC CAI (Already purchased)
Vibrant headers
CA 3" Downpipe w/high flow cat
Vibrant 3" Exhaust
-Will have exhaust shop cut the collector in the header so it's 3" all the way back
CA Front Mount heat exchanger
CA Dual Pass Intercooler plate kit
Snow performance water/meth injection kit
CA Stage 3
-2.7 ZZP Interchangeable Pulley system , 1 step colder ngk IRIDIUM spark plugs , GM shortened belt , 42# Lucas Injectors , Injector Wiring Harness, Stage #3 Retune

 

a 2.7 pulley is way way way too small for 42lb injectors. You'll need 60's to go that small.

Also.. get your car custom dyno tuned by someone... otherwise you are going to have trouble.