What is the best springs for performance. I don't care how it looks I want it to handle like its on rails.

 

i woudl say the coilover system that rksport has

 

Pretty much any full coilover system..... meaning a full strut/coilover combo.

 

I'll go one step further, any fully adjustable coilover kit. Makes it easy to get the suspension tuned EXACTLY how you want it, you can have it "on rails" and super stiff when you want it, but then you can soften it up for daily driving.

 

We have one set of the Eibach pro kit for a very reasonable price. Has a higher spring rate than the stock springs, and lowers the car some. Let us know if you have any questions. We also can get the RKSport coil overs.

 

What ever you do order it from TurboTech. they RULE!

 

it seems to me that any coilover is going to require massive modification to the rear suspension because of the way it is set up, the current rear dampners are not inside the current springs rather they are infront of them, yes the cobalt cup cars do have coilovers but they did custom mounting of them and had to use a bunch of parts off of other gm cars! I dunno maybe i am crazy but i dont see how you could bolt coilovers to the rear!

 

eibach sportlines are amazing springs i had them on my civic, and ill be upgrading to them on my cobalt in short time

 

The "massive" modifications to the rear of the GAC SS weren't for the coilovers, they were in order to change bolt patterns, put on smaller tires w/a different offset, and coilover conversion from a different car. The only thing they did was drill/sleeve the beam in the back for roll adjustment and relocated the shock mounts since the Ohlins that they used were not built for the Cobalt. A Cobalt coilover will be made to fit our stock suspension, eliminating the need for any modifications.

 

Sportlines are good for street use or drag use and make the car look nice, but for performance like the original poster wanted, adjustable coilovers are the way to go.