Let me know which stuff your looking for and I'll try and pm info/links to you. Some of the stuff can be seen in my picks. Others I still have to add to my picks.

Mike

What I did
 

Spend under 50 bucks. Bought a Thrush. Cut off that soft ass muffler, and placed it there. Done it to every car Ive had with the 2.2 ecotec 02 cavalier 08 colbalt and now the 11 HHR.

You did see the Op started this thread 11 years ago, he hasn’t been on the site since March 13 2017. But good information about your muffler installs.

I know this is an old thread, but I’m a new HHR owner so I’m taking the liberty of freshening it up, especially since there are great idea in this thread, old or not.

1. Add a nice license plate frame – especially effective since the space for the plate is pretty large and up high compared to other vehicles.
2. Add interior LED lighting – all the dome lights are the same, just make sure you get 42mm instead of 44mm like some LED sellers recommend.
3. Add exterior LED lighting – keep it simple with just the license plate lights, the corner lights, and the backup (reverse) lights. Adding anything else will require resistors or other stuff you really don’t want to bother with.
4. Paint your bow ties – I know some folks prefer overlays but they didn’t work for me – painting is actually simpler and cheaper to me and you’ll get better and more permanent results.
5. Add an exhaust tip – chrome or black, just make sure you get stainless steel or you’ll be buying another one soon.
6. Add accent trim (door and mirrors) – Add chrome if you want or black as a contrast to your body color.
7. Paint your steel wheels – Easy to do with steel wheels. You can use the “deck of cards” technique where you use the cards inserted around the rim so you don’t have to take the tires off the wheel.
I wish clear corner lights were still available for the HHR. I found front ones but not rear. They look great on silver or black cars. Hopefully some will pop up on eBay or CL.

Good tips for mods to an HHR, it never gets old! If you decide to install LED front turn signals , install 50 watt resistors to stop the hyper flash for the rear I installed IPCW Ruby red led lights, no hyper flashing!

Don't forget the "Gutter-guard" grille mod.

$25 ram air hood
 

2 toilet flanges, foam weatherstrip,
https://cimg7.ibsrv.net/gimg/www.che...42888fa0fb.jpg
8" of dryer vent a
https://cimg5.ibsrv.net/gimg/www.che...f9841a9a41.jpg
https://cimg4.ibsrv.net/gimg/www.che...28073527fb.jpg
https://cimg1.ibsrv.net/gimg/www.che...3d7ea66026.jpg
https://cimg3.ibsrv.net/gimg/www.che...7256f9e985.png
nd a $15 hood scoop.

Picture with the hood down ?

https://cimg3.ibsrv.net/gimg/www.che...7aef077c6.jpeg
This is the hood closed shot , but the scoop hasn’t been installed yet