[jblackburn]

-Forged pistons
-Bigger turbo
-Valve springs
-Bigger injectors
-E85?

Once you've done that and still want more, then you can look into cams - no one has found the need yet, and VVT can do some pretty cool stuff (that's why they went through the trouble of putting it there). Those mods will put a Cruze well into the 200 HP range.

 

[jblackburn]

You should start by talking with your personal GM tuner, because a good tune on your stock car can easily make an extra 25% more power and torque right off the bat. Otherwise you should get in touch with @jblackburn because he seems to know his stuff.

You can find Walker Morgan on Facebook in the Sonic groups. He would be the one to really get in touch with, as he's taken a Sonic over 300 HP [relatively] reliably.