As you are comparing different springs the Eibach pro kit will give
you a 1.5" drop all around and the H&R supersports will give you
more like 1.75"-2" so,the Eibach sportline kit would compare better
because the drop is somewhat the same in inchs.You didn't give
your stangs year or if it's a coupe or vert.The spring rate of the
Eibach pro kit for the 94 and up 4.6L coupe is 460-570 front and
200-250 rear.If you have a vert.The 96 and up 4.6L vert. spring
rate is 450-575 front and 170-315 rear.So,compare the Eibach
spring rate with the H&R supersport spring rate as GDawg stated
(700-760 in front and 275-300 rear) you come up with two different
drops on your stang.The Eibach 1.25"-1.5" all around and the H&R's SS
1.75"-2".The H&R's will be stiffer and the Eibach's will be alittle less
stiffer as they are totaly to different springs.I recommed the following
accessories with your springs offset steering rack bushings,rear bump
stop bushing,and caster chamber plates.Your springs will settle in two
weeks to a month and I would subjust a four wheel alignment after
this time or you could get unwanted tire,shock,and strut wear if not done.
When changing springs it would be a great time to get new shocks and struts
since everthing will be apart as time go's on they will both wear out one day.
In my opnion I would get H&R supersport because they will fill the wheel we'lls
and performance nice and smooth! GDawgs' GT looks great with his H&R's SS's!
