Bought these new shortly after I bought my Mustang but had to sell her I opened the box to look at them but never installed. Steeda part number is 555-8215, you can find the details on Steeda.com or you can check out the link below. Steeda Sport Springs for 2005 and Up Ford Mustang 555-8216 New on the site are $272.95 + s&h. I'm asking $250 shipped!!! Open to offers and trades! Located near Raleigh, N.C. Phil - 919-346-3410 Thanks!
According to Steeda about 1" in the front and 1 1/4" in the rear. It's a nice mild upgrade as far as handling goes from what I've read.