I didn't buy a header for my car.I think that it might be the next step for more performance for me -but not right now.
I know that the Cobalt and Sky/Solstice forums are a good place to get more performance info on the Ecotec engines we all share.One guy had his cams reground and said he made big power gains.Obviously this step is a big one and not something most of us would consider doing.If this kind of performance is what you want, then check out these sites too.

 

Has anyone tryed doing a few runs with each application? Let's see some actual 1/4 mile times.

 

A new question if you had it to do all over again and wanted to add power to your HHR What would you do and what order would you do it in.

Intake
Header
Exhaust
Muffler
Tune
Pully

 

I installed the Airaide intake and noticed gains all around. Quicker starts. More torque and more passing power. now whem I say more I don't mean like 50HP. Maybe 8 at the most but I do notice the difference. Not much of a MPG increase with regular unleaded but if I run super it never drops below 30 mpg.
Sounds really cool too.

 

I think I am going to stat off with the K&N setup For my first realy mod to my car.