Just thought I would give a review of the springs I installed on my 2013 GT/CS. The car is a daily driver and has to ride well while not being harsh. It has the stock 19's and awful Pirelli P-Zero Nero 245/45/19's.
I bought the Vogtland GT Leveling Kit. .8f/1.2r and Koni STR.T's(Yellows), a J&M(Founders Racing) Panhard bar and Eibach camber bolts.
Vogtland is the maker(my understanding) of the Steeda Ultralight springs.I believe the spring rates are slightly different but not by much and of course the drop amount is different.
Vogtland lists 4 kits..A V6, A V6 Leveling, a GT and GT leveling each with different drops. It is my understanding that the way they get the different amount of drop is with different front spring rates. The rears are all the same.
I got the Koni STR.T's at Hypermotive performance on sale.
This is the panhard bar I used. It is made by Founders Racing and seems to be a good quality piece with grease fittings and easy adjustment and Poly ends.
And last but not least the Eibach Camber bolts. I think enough has been said about those.
Install was easy and I am VERY happy with the drop and the ride. The camber was -1.7 and -1.5. The bolts brought it back to -.5 on both sides so well within specs
The car sits at 28.5 front and 28.5 rear with a full tank of gas. The drop was exactly as promised.
Much less body roll, less brake nose dive, better cornering and not ridiculously low.
I have noticed less noise from the crappy Pirelli tires going over expansion joints, bumps etc.
Now to the ride....the stock springs and shocks were, in my opinion, very abrupt during suspension changes. It rides SMOOTHER THAN STOCK. Now that is not to say it isn't firmer than stock. But no harshness, just feels better. It is hard to explain ride quality in general but I am extremely pleased with the results.
All together I put app. $700 into it and I love it.
Hope this helps if you are considering lowering.
Moderators: I meant to post this here but ended up posting it in the S197 handling section. Sorry about the double post but you can remove the other if you want.