The Steeda is like 28.6mm--I have some concerns at 24mm with the rear LCA's--not to mention 25mm on the Eibach bar. That Steeda bar is over-the-top-big.
We tried a 7/8 and 1" rear bar at the racetrack before settling on the 1-1/8 inch bar that we use now. The car turns faster lap times with the 1 1/8 bar.
A lot depends on the rest of your combination. Our spring rates are not as high as some of the kits I have seen (H&R race springs come to mind), so the stiff rear bar may work better with our springs than someone with, say, 375 lb rear springs.
Before upgrading the rear swaybar, in our racecar one of the biggest limiting factors was understeer and lack of traction coming out of corners. We used to spin the inside tire around turn 10 at Moroso and turn 4 at Homestead. The 1-1/8 rear swaybar solved the traction problems and improved segment times through other parts of the track as well.
Granted, the bar may make the car a little too squirrelly for an inexperienced driver on the street, but it is definitely not overkill on the racetrack. The fastest front wheel drive racecars usually have such a stiff rear bar that they corner on three wheels with the inside rear wheel hanging in the air. Our rear bar is not quite that stiff, and our racecar still corners on 4 wheels, but that is the direction to go if you want to be fastest around the racetrack.
