Wondering what the difference in ride quality is like between the two setups.

I currently have the Koni yellow adjustable shocks and Eibach Pro kit springs.

Love the combo and actually perform compared to most cheap coilovers out there.

I am wanting to possibly get the ground control coilover springs for the koni shocks since I would like the rear to be a little bit lower.
Just wondering if the ground control springs drastically change the ride quality or anything?
Or is it very similar seeing as they are still Eibach springs but are a different type of spring I believe.

 

Ride quality is a function of a few things. At any one corner, the shock determines how that corner reacts to bumps, not the spring. Take the car as a whole and now you are talking about ride frequencies, which are a function of the springs. So, putting a relatively stiffer spring on the rear of the car will provide a more comfortable ride vs stiffer in the front.

Picking between different brands of springs does not need to be about this brand or that brand. Pick springs that meet your spring rate/length/diameter needs. Hypercoil makes the best springs because they are guaranteed to be within 2% of the designed spring rate and lenght. Most other brands do not have this guarantee. More than one of my car setup books swear by hypercoil for this reason alone.

 

Don't the ground control coilovers need to use the springs they come with? Seen them being sold together only so would assume I would be getting those springs instead of my current pro kit springs.

 

No. No springs/shocks/coilovers have to use the springs companies want to sell you. Real springs (not lowering springs) are very universal. The only thing that has to match is the inner diameter of the spring to the spring perch.

 

Ah ok. How are the ground control springs? Would rather just get them as it seems like you have to pay for them when you buy the ground control coilovers anyways. Haven't seen them separate.

 

Ground control should tell you about the springs. If they don't, assume they are hiding the facts. You can just buy the koni sleeve and upper/lower perches and then get whatever spring you want.

 

I'm looking at getting a used set of them. Springs are the regular eibach springs they usually come with. 450, 400 I think.

 

GC uses Eibach coil springs call eibach and they can help you get the right ones.