the ttr bar is 25.4 mm and stock is 33mm. why is the ttr stiffer if its thinner.
thx dave

 

I think you are comparing the TTR rear sway to the front stock bar.(correct me if I'm wrong) The HHR does not come stock with a rear sway bar.

 

It is a torsion bar it twists, adding the 1" TTR stiffens that twist up. I had it for a while, made the tail really flat, but caused the front to push, I really noticed the difference when I took it off to sell it. It is my opinion the stock SS handles better without it, GMPD made it well. well actually it was a little more than two cents.

 

my bad , torsion bar, similar idea. thanks

 

Our bar is an "add on" you still keep the internal factory one.