Maybe someone has already done this, I'm currently running 215/50R-17 tires, I'd like a little more sidewall height so I'm thinking of using 215/60R-17, anybody see a problem doing this on a 2008 HHR LT, everything stock.

 

215/60/17 specs out on a tire size calculator to 27.16 inches. That's too tall for the HHR as it will hit the lower strut perch on the fronts.

26.3 inches is generally about as tall as you can go with stock offset rims.

 

Here's a calculator that will give you an idea of what you could change to, and the impact on your speedometer and such.

Tire Size Calculator