im runnin impala ss springs, but im not sure how much it dropped cause i bought it with cheap lowerin springs in it. pic in my sig is with ss rear springs and 2" drop spindles w stock springs in front. iam goin to SS springs in the front as well to get a little more rake right now its sits level
I cant speak for everyone who did this, but my springs were definitely shorter than the ss springs. i thought maybe i would still get a drop, but they didnt give much, and i was an inch or so higher after installing them. they ride pretty good though, and since i threw a couple hundred pounds of audio in the back, it seemed to level the rear end back out.