my H&R's measure ~ the same a year after I measured them when they were like 3-4 weeks old.
a spring should not continue to sag & get lower & lower, yeah. I know you guys may think you like that cause your lower, but this is not what a spring should do really, maybe after 5-7+ years of service, but not every few months it's a bit lower, a year later it's noticably lower?... this seems like fatique from being overloaded to me.
the definition of a spring is being able to be compressed without altering it's load carrying ability & to retain it's length over time... a well designed for the application spring should not continue to sag lower & lower... if it does it's overloaded, which in my opinion the eibachs are overloaded in this application on the fx, I'm no engineer but it seems pretty obvious to me, deny all you want, but facts are facts, & it's a fact that the eibachs do sag more than they should as time goes by where they should not & it's a fact that some of them have broke...
it's also a fact that eibach has many thousands of happy eibach owners, but realize that as far as FX specific aplications alone go's, there are probably only a few hundred if that out there, & having several snap is an indication of something that really can't or at least shouldn't be ignored. I belive they are simply overloaded...
also, realize that you can only go so low before you run out of strut/shock travel. it's not as easy as just making a spring to give you 2.5" of drop & bang, your 2.5" lower. our struts in the front only have 6" of total travel, that's up AND down travel, rears similar. factory places the ride hieght at a bit above center of travel in the front, so this means that a stock fx has slightly more that 3.5" of travel before the front strut bottoms...
now you go & do a H&R drop, take ~1.2 from that 3.5 & you still have 2.3" travel on compression which is adiquate without a much higher spring rate... eibachs maybe are going to give ~.5" more drop give or take, so now were talking about ~1.7 from that 3.5" total compression travel, leaving ~ 1.8" of bump travel. eibachs NEED to be stiffer to be able to work with the 1.8" travel without bottoming hard. you just can not go & make a spring with another .5" drop over the eibachs without increasing the spring rate dramatically & making them much stiffer than even the eibachs. if you only left 1.3" of wheel travel you will either need a spring approching the 500lb spring rate or you will bottom the strut, when the strut bottoms you loose all travel & the results are very unstable & very unsafe at higher speed agressive manuvering, this is just not how a suspension should work...
if you research what many of the road racers do, you'll find that sectioning the struts is a very popular mod, this is where you actually shorten the strut by approx the same amount or close to it as the amount you are dropping the car. this retains the bump travel so the strut does not bottom even at much reduced ride heights. our fx strut is the equivelent of ~15" strut cartridge in the front. if the strut was sectioned to 13" insert, then dropped 2.5", the resulting wheel travel would still be ~3", more than enough, where just a bit over 1" travel is just not enough travel.
the strut mod that moves the strut down in relation to the wheel is great because it is taking ride hieght out without reducing wheel travel. it is the equivelent of sectioning the strut without actually having to section the strut...
in my opinion the eibachs are about as low as the factory shocks & struts can handle, to go significanly lower is just not practical with just a spring swap no matter what other spring is built & no matter who builds it. a spring alone is not the answer to getting much lower than the eibachs, the rear shocks already are at there limits & will bottom from time to time with eibachs alone, fronts are not far behind.
for just springs alone to give more drop there going to have to be much stiffer & then we run into the next problem which is, the factory or factory replacement type struts & shocks are not valved for these higher spring rates at all... even the rate of the eibachs is quite a bit higher than the struts/shocks are valved for... having struts/shocks that are valved lighter than they should be for the spring they are mated to is what's going to cause side hop or walking sideways on bumpy aggressive higher speed turns... I'm sure you can all see that the fx suffers from this in the rear badly enough even with the stock springs, adding stiffer springs in the back only worsens this condition, bottom line is theres more to dropping than just dropped springs if you want to also be able to drive it aggressively & have it handle well, if you just want it low & choppy & don't mind skipping around through bumpy turns then fine, but this is not how a good suspension is supposed to work. I could go on & on, but I'll save that for the suspension mod thread
