Completed K&N Aircharger intake mod on my son's '08 Pontiac Grand Prix GXP. A few comments about the install. The pictorial instructions are comprehensive but vague on the hardware like washers, bolts, nuts, etc. so you have to reference the parts illustration which is hard to read at times. The rubber grommet fasteners for the two bolts that hold the heat shield and ECM tray to the inner fenderwell seem flaky but work. Overall the mod was time consuming but fairly easy to do. What real benefit remains to be seen until a power tune is done or a few runs at the dragstrip. If you like intake roar/noise then you will get plenty of that.
Also, the rubber seal needs to be cut to fit the heat shield but hi-temp RTV silicone sealant should be used to keep the seal intact. One pic shows we have 100 mph tape holding one part of the seal down.
Last comment. The ECM and TCM will be more exposed compared to the stock airbox.
