sway bar lengths?
 

Anyone know the difference that sway bar lengths will have on the frs/brz.
For example Cusco has 2 front sway bars; 16 and 22. What is the difference?

That's the thickness in mm (not length).
22 mm has a much higher torsion stiffness than 16mm.
If they were solid rods the 22 mm rod would be 260% stiffer than the 16 mm rod.

I think your sums are a bit wrong there.

well dang i was ignorant. But what does the thickness have to do with handling?

Torsional resistance is proportional to the diameter^3.

Example: Doubling the diameter of a rod doesn't just double its torsional stiffness but increases it by a factor of 8.

Increasing the stiffness of the swaybar reduces body roll.

Also, increasing swaybar stiffness in the front increases under-steer.
And increasing swaybar stiffness in the rear increases over-steer.

what if you want to have the same settings as stock but stiffer sway bars?

Then you would need to increase swaybar stiffness in the front and rear equally (replace front and rear sway bar).

Body roll will be reduced but the suspension will be stiffer and for instance have more difficulties to deal with potholes.

cool thanks for the much needed info :D!

Incorrect, it's ^4 (for a solid bar).

A 22mm bar is approx 360% stiffer than 16mm one. Of course once you factor in your lever arms etc. that figure goes out the window, but for a straight bar it's correct.

You're right. I mixed it up with torsional tension which is proportional to d^-3.

Isn't one of the Cusco sway bars tubular?