I am in the process of building a combo daily/ track/ AutoX build and I have the Progress Technology CS2 coil-over kit and 24mm rear swaybar. I ran the car at Streets of Willow as a shakedown and I was very happy with the performance for an out of the box setup, but I want to increase the spring rates.

I already have a variety of spring rates for the rear that are RSX standard linear coilover springs, but I am curious what I may need to put those in since the rear is a progressive spring with the upper OD of the factory springs.

Does anyone have experience with doing this?

 

I'm not sure I understand what you mean by "the upper OD of the factory springs," but maybe I can help with what knowledge I have of the RSX vs the 8th Gen Civic.

Apparently the motion ratio of the RSX is such that spring rates have to be much higher for the same "stiffness" (since I don't know the technical term) when compared to the 8th Gen Civic.

Out of curiousity why do you want to increase the spring rates? Does the car have too much dive/roll in braking/corners?

 

The springs that come in the Progress Technology kit are tapered, so the utilize the factory upper spring isolator. For me to run high spring rates with traditional coilover springs I need to find a way to make them fit the upper mount. I am going to change the valving to match the spring rates once I figure this out.

I am thinking I might be able to flip the whole assembly and run the adjuster on top instead of the bottom, but Not sure that will work. This is what it looks like below



The rear rate is 450lbs at the moment, so I want to increase it to help with rotation and reduce body roll.

Just trying to see if anyone has delt with this before.

 

Suspension design is a little different on the 2 cars I just mentioned I have RSX coilover springs because that's what they were for, but they are just a standard coilover spring.

I want to change it to reduce the body roll and also to help get more rotation out of the chassis.

I tried posting a photo of the way the adjuster looks, but I may not have rights to do that yet. (It went to a moderator for review. )

I am thinking I can flip my entire spring and adjuster assembly and that may solve my issue. Just wanted to see if anyone has done this before. This link shows photos if the rear suspension design by Progress.

Progress Rear Suspension

 

Oh, I see wow that's a weird spring. I didn't know they use progressive springs back there.

 

Yeah, my idea makes it look like the redshift Motorsports rear design so it should work in theory. I just figured before I tear it apart to test maybe someone already knows what to do. That spring is a 450lbs rate. I already increased the front a tad to 300lbs, but I need to get something stiffer on the rear suspension.