when you bolt them up, its not something you can do in less than an hour. You will have to lift the vehicle once the back bolts of the header-block are removed, your gonna have to do it by touch, there should be 8 total studs to remove...Ensure you pull them straight out and not at an angle.
next there are 3 bolts that the downpipe flange onto, you want to remove the whole downpipe-catback (2 bolts) enough to loosen to roughly 3" of play. Once that's loose, you want to get the heat shield bottom bolt loose, do not bend it (highly recommend doing this before loosening the header 3 bolt triangle bolts). Once that's all done and I also to highly encourage using OEM new gaskets (header-block gasket and header-downpipe gasket). Once its all bolted up start with middle bolts for torque and work your way outward to ensure the gaskets are properly sealed.
Now have a drink and let the good times roll. Your OEM fuel maps will increase on PIDs through a high end scan tool of +8, +3, and +10 from 1800-2700 rpms. Now its time to tune your block to ensure your PCM is settled for long term fuel trim and do not tune until after 2 weeks of driving. Fuel trim is doing adaptive strategy during the time being.
Forgot to add, Its run by Brad Mabry aka Bad Mab...It may take up to a few weeks, depending on if you have Air injection on your exhaust manifold, he does a wonderful job for hand made, check out my Vehicle showoff to see it sir.
2009 Cobalt LS XFE U74
Mods: K&N Typhoon Intake, Option Cat-Back Exhaust, Cosmo Short shifter, Maxxim Ahead 17X7's, MPx shorty antenna, FE5 Strut/shocks, Tein S Techs, Moog endlinks, Moog spring seaters, ZZP shorty header, LSJ downpipe, LNF front grille
Last edited by 5t3alth; 09-20-2013 at 01:45 PM.