Another quick Q for you knowledgeable guys. I searched for it, but came up empty. I have a 97es v6.  I am minor upgrading/replacing the stuts and springs on my car. I am installing simple new KYBs with new stock springs. My question is... what is the spring rate difference for the oem convertable sebring springs vs. oem avenger springs? Any diff in height or stiffness? I want to keep the car at somewhat stock height. Thank you for you answers. This is a great forum!

thanks again for a fast reply...  a follow up.  Are the whole strut assemblies/perches then non-interchangable as well? I assume they will not work.....Are there any options for a stiffer OEM setup from the eagle/mitsubishi line to fit an avenger? If so... what rates are we talking? If not, and I am stuck with the dodge oems, I will make do.  I come from and know Subarus(dont laugh) very well. I am used to extreme interchange flexibility and am really unfamiliar with these cars as of today. I will have this thing in pieces once the snow melts up here to learn then inside and out. I hope to learn a bunch from this board, thanks for having patience with me

OK You want to lower your car , First off how do you drive it ....
Is the car a daily driver ?? or is it an all out show car??Is the car kitted??what are your local roads like??Snow and ice in the winter?? All of these will influence what type of lowering you might want ...
For a Daily driver I highly suggest a Drop spring , less maintenance/more reliable/Easier on the wallet
All out show car/kitted Think about coilovers or the Tiens for adjustability , ability to slam at shows
Bad local roads /big potholes/steep drives/roadkill galore think of a lesser drop or coilovers/tiens
Snow and ice in winter /think coilovers or tiens for ability to raise it back up for winter(will require alignment)

OK Now What do I need:
Lowering springs that WORK:
Eibach pro kit 1.8" drop settles to about a 2" drop
Suspension Techniques 1.3" drop settles to about 1.75" drop
Intrax 2" drop settles to around 3" drop or more
Dropzone 2" drop settles to 3" or more
OK these are from MY experience on a V6 ... I HIGHLY recommend either the Eibach Pro kit or the Suspension Tech springs... They provide the BEST stock like ride and are VERY drivable on less then perfect roads...
IMO The Intrax and Dropzone springs are VERY VERY low and VERY VERY bouncy
they seem to be remarketed Eclipse springs that have too low of a spring rate to handle the V6 ...

Coilovers that WORK:
Maxspeed/Dreamspeed coilovers
SkunkII Coilovers
These provide good spring rates/driveability and adjustability... They Require an experienced installer to give best results...Poor installation you will have noises bumps rattles ect that will never go away ... Properly installed they are descent but require modification of the struts that VOID warranty...
I DO NOT suggest getting no name ebay coilovers for the eclipse , With too low of spring rates they WILL collapse/They will ride poorly/You will end up replacing them ... Even some Named coilovers will not hold Up , I purchased a set of WeaponR's and they were junk after 3 months...

Tien all in one unit
These include coilovers AND Strut combo's built together ...These are 95/99Eclipse parts but have a high enough spring rate to work
These have great spring rates, are made as a unit so you do not have to assemble them are very reliable and easy to replace the entire suspension...There are several Tien units from the basic to the EDFC adjustable

Struts:
Will I need Struts , YES any lowering will require struts... Can I use my stock struts?? Yes but they will blow and be worthless in no time...So WHY bother, I don't care if you are broke, save your money do it once and do it right !!!
KYB GR2's are very inexpensive CAN be used , But IMO they are not the RIGHT choice they are basically Upgraded stockers... Many have used them , but they fail pretty soon on Springs that are 2" or more, Same with coilovers

KYB AGX's Are more money/more adjustable hold up well to being lowered/ there are two part#'s one for 2" lower one for lower then 2" The lower set is better for coilover use as they have a shorter rod and prevent BOTTOMING...

Koni and Tokkiko both make excellent struts but are normally more expensive and harder to find...

Camber Kits:
After lowering will I need a Camber kit YES you will definately need at least a REAR KIT, this can be done with longer bolts and washers, OR you can purchase a premade kit
Will I need a front kit POSSIBLY I've dropped numerous cars for members/non members and here's what I have found, I've seen 1.3" springs require no kit to up to a 3 degree kit ... What I suggest is dropping the car/let springs settle for at least a week then take the car in for an alignment check, they can then get the car up on a rack and TELL you what kit you will need.... Do your homework on the alignment shop ask locals with local cars that are dropped where they got the alignments done... Try to use a shop thats used to lowered cars and able to get them up on the ramp...

OK how much will all this cost me
Plan on spending around $1000 on parts/alignment ... If you are not a do it yourselfer then add $300 for labor to install some shops will be more/less depending on your area.. Of course those prices are new parts , you might be able to get a deal on used parts but remember you can't be sure on used struts...

You can also run KYB GR2's on one side and the KYB AGX's on the other side as they are adjustable/stiffer