How much will 4 cyl. springs lower my stang?

I have a 90 hatch which has eibach sportline springs and the drop is perfect. The only problem I have with them is at the track and is killing my short times (high 1.8's). Currently I have strange 10 way adjustable struts, no sway bar, rear upper and lower control arms, mm subframes, with 275/50/15 MT drag radials and stock rear shocks. I plan on getting the strange rear adjustables soon. My best e.t. is 12.58 at 110 with a 1.87 short time. I'm pushing 325 rwhp which I think can get into a 12 flat at least with the right suspension. I was planning on running 4 cyl. springs up front with half a coil cut out. I was wondering if any fox owners have installed 4 cyl. springs with a half coil cut and if they used the coil isolaters. If so how much did it lower your stang? My eibach springs are too stiff of a rate to improve my 60 footers. Sorry for such a long write...I just need some opinions b4 I do it and waste my time. Thanks in advance
 
four cyl spring are going to kill your ride, as will most drag springs, keep your sportslines and buy drag springs for the track. if your not to keen on the swaping springs get adj rear controls, progressive springs and tweak your ride you might also want to look in to reduilding your posi the clutches in your liumited slip could be going out it is 17 years old.