Joe Z

iTrader: (10)

Ok Gang...

What I need to know is the technical differences on the F-Sport Lowering Springs when compared to the Eibach Springs..

First, I have to disclose that I have an IS350 with Sport Suspension..

What kind of drop can I expect when removing my OEM Sport Suspension springs and upgrading to either of these ??

Next, does anyone have all the Spec data comparison for both of these??

and

Finally, how well will my OEM Sport Suspension Struts work in conjunction with either of these springs??

Thanks in advance for the help..!

Joe Z

P.S. - I'm a newb when it comes to lowering my car... never had to and never planned too.... till recently...

ba-b4

Not 100% sure on the exact lowering but approximately the F sport springs will lower your car 1" all around for the standard suspension but Eibach's lower the front by an additional 1/2" because the front wheel gap is bigger than the rears. I don't think that by making it all even all around is necessarily for a functional reason it's just that people want it that way for appearance.

Your sport suspension is already lower by 1/2" I think than the standard suspension so the F sports will only make your ride another 1/2" lower all around I think. Eibachs will make your front go down about 1 whole inch in the front.

It's stated that the f sport springs can be used with the stock standard shocks so it should be no problem on your sport shocks too. I got the Bilesteins anyway just to be safe though.

projectdna

iTrader: (56)

your OEM sport suspension struts will work fine w/ either of those springs. i'm running tein s-techs w/ OEM sport suspension struts, and the car feels and handles like the way the sports package suspension is supposed to feel. the lowered ride height is a bonus too.

btw (and fyi), your alignment will not be affected with the lowered right height as a result of the f-sport or eibach pro-kit springs. (just remember to do the alignment after the springs settle...)

llamaboiz

Ok... on the 'looks' side of this, Fsport/Eibach (350) lower about the same, IF you run 18" rims they will actually APPEAR to take up more wheel gap than if you have 19" rims, why i dunno but after i switched to 19" rims i wasnt satisfied with the drop anymore.

IMO: i would suggest you either go straight to airrunner or coils at the least... BECAUSE you WILL eventually go down this path I recomend Tein SS because it can drop lower than CS. I know Megans can go lower but... i prefer Tein and SS is way cheeper. As for SS adjustments, they can go just as comfy as CS so dont let the 'comfort sport' fool you.

VikH

iTrader: (5)

Joe,
My F-Sports lowered me 1 inch when installed. I am assuming it will settle a bit lower. Car handles great.

Vik

FMJ IS

Vik, did you do a measurement recently? did it drop more than 1" after it settle?

if you didn't measure, how many fingers in the gap now?

VikH

iTrader: (5)

You can barely fit your hand under the rear. I would say .5 to 1 finger in the rear and 1.5 in the front. I did not measure when I first received them, but another member who did measure stated it was a 1 inch drop initially.

eskae3

iTrader: (15)

Joe,
I had purchased the Eibachs but changed my mind on installing them because of the larger drop compared to the F-Sport so I went with the F-Sport. But now I get the clunk noise in the rear ONLY when going over speed bumps above a certain speed.

The following are spring rates info i've seen on the forum are:
From what i hear the spring rates of the Sport springs are the same but just sit lower by .5 inch. The F-Sport are designed to work with your stock OEM struts.
Since the spring rates of the F-Sport are intially lower than the OEM, you get a softer ride when the springs get initially displaced but as they get into the secondary coils they will be stiffer than the straight wound OEM springs.
Personally, I like the handling drop after the F-Sport. They are comfortable and when corning at high speeds, you get the stiffness that you need with the progressive spring rate.

Navigatn

some people like the harsh stiff ride on their suspension so they can corner on rails (no body roll). but the downside of stiff suspension is that you will feel every bump on the road.

If you purely going for cosemetics, then you should find a set of springs that are close to stock spring rates to give it that stock feel.

Also keep in mind that the more you lower your car, the less suspension travel you will have on shocks, thus risking hitting the bumpstops. So for a set of springs that slams your car, they will need to be stiffer to keep you off your bumpstops, but that leads to the bouncy harsh ride you see sometimes. I believe eibachs are progressive which means they are stiffer as they become more compressed.

I haven't researched the F-sport springs much, but from the reviews, they seem to be best matched for your suspension, since your sport suspension shocks are valved to be a bit stiffer than reg shocks. The only gripe I have with them is that they appear (to me at least) to have a saggy rear.

since you already have sports suspension, I would go with the f springs and later upgrade to the f shocks for optimal performance.

/ninja edit

and i believe the ride height specs are quoted for reg suspension. so in your case with the sports suspension, you would have to adjust for the 10mm diff in the front.

sincityIS

These cars don't have a saggy rear, it is because the rear tire is a lot bigger taking up more space in the wheel well.
I installed 235/40/18 tires up front with 255/40/18 rear on stock suspension and it almost looks even now. If there were a 255 tire up front as well then I think the front may actually be a smidge lower looking.

FiveOhNine

255 up front would be awesome if it fit.

lobuxracer

iTrader: (2)

Actually for a car this heavy 315s all around would be appropriate.

sincityIS

I don' t even know how much it weighs, How much does it weigh?

llamaboiz

what... the car? on paper 3600ish but irl? probally heavier with all the junk in the trunk (for the car and the person driving it )

sincityIS

That is kinda heavy, but any lighter and it would not be as solid.