A bit tricky to install but it will fit a Ponitac G8
This will fit a 2008 - 09 Pontiac G8 GT. The plastic housing in the car has a frame all the way around that the filter must sit flush against. The bottom edge should go in first and then the other sides need to be jostled around a bit to get it just right. It took about of trial and error but it did eventually work. It should seal fine and not let much air bypass the filter.