Och

iTrader: (3)

If I get a set of billstein sports to replace the factory shocks, but keep the factory springs? I do not want to change the ride height, but seek some handling improvement.

JiBBeL

iTrader: (2)

You'll notice a difference. Depending on what your definition of "better" is in terms of handling, it may be better to you. It'll be stiffer with the Bilstein's with a bit more road-feel. If you're doing the work to put on new shocks though, get a sportier spring with a very mild drop to really get the most outta it.

Och

iTrader: (3)

It seems that even the most mild springs are more than an inch of drop, which affects suspension geometry.

ZippyGuy

iTrader: (9)

Actually, that is incorrect. Any suspension modification affects suspension geomtry, even installing new shocks, tires, etc. That's why you have the car aligned after modifications.

You can "safely" lower the car 30mm before the suspension geometry becomes negatively affected. A slight lowering will enhance your handling characterics once you have an alignment, which should be done once you've completed your shock replacement anyway. Anyone who lowers more than 30mm has negatively affected the geometry and should look at either a camber kit and/or RCAs.

I can understand your hesitation with replacing the springs to aftermarket, but I assure you, you will LOVE the handling/feel with Bilstein HD's and a progressive lowering spring like Eibach.

GSteg

iTrader: (15)

With new Bilsteins, you're definitely going to have a slight firmer ride. On turns, it'll initially feel less spongy, but ultimately, you're going to have the same body roll as before.

sam430

iTrader: (10)

I have bilstien front with stock spring and stock back with stock spring... the front will be stiffer. It's pretty good I think but will not be better than the swaybar route.

You will need swaybar to compliment it.