The J body Cordobas share a common front end with all the other sibling cars. Factory sway bar diameter is 1 1/16". The cop cars came with a 1 1/8" front bar and a 3/4" rear bar. Changing just the front made a significant change in my four door and adding the rear afterwards was night and day. Simple lane changing on the express way was honestly safer. The car would take exit and onramps much better without burying the corner of the bumper into the pavement.
My Dad's coupe which is pretty much the same thing as what you have had the exact same experience. Factory AHB/cop car sway bars are one hell of an upgrade if you can get your hands on them. Don't forget to grab the shock plates as the civi cars don't have provisions for the end links.