i just bought the popcharger/ztube combo and going to install it tomorrow. i was reading the instructions, and it says that i have to use the oem stock scoop to connect with the heatshield? what's that? am i supposed to have it already? because i'm currently using the long-ram AEM CAI (installed a long time ago) and i'm not sure if it's in the car

what is a long ram setup? You mean a cold air intake? There is short ram like the popcharger/ztube and there is the full coil air setup which the filter sits near the bottom of the bumper.

If you have the cold air setup you were supposed to remove quite a bit of plastic crap out of the way. One is a plate which you would be able to see in the bottom right lower mesh part of the bumper. From there a plastic tube connects that little box to another small plastic box which sits behind the radiator. That little plastic box connects to the OEM air box. The only thing the popcharger and z tube replace and get rid is the tube that connects the OEM air box to the throttle body and the OEM air box. You need all of the other stock intake components in there and your new popcharger box connects to the little plastic box which sits behind the radiator.

Hope this helps you out!!