For his 20 years, I make a refresh of the suspension because he was in great need. I started with the rear ones as the 2 springs were broken in the top. :S No OEM can't be found anymore except used ones. I check on Rockauto and saw progressive Moog cargo coils (CC859) which it's said on V8SHO that they are an upgrade but will add a lot of stiffness to the rear and are a good answer for a SAS. Finally put them with the SARC struts but give me first a way too much HNV with my 25mm rear sway bar (but with 0% of body roll). Each rear wheel going on a bump can activate SARC on the 2 rear wheel at the time...(at least it's the feeling I had). I changed the bar for a 21mm and give a real great feeling, stability and some more infos from the road from the stock configuration (with maybe 10-15% of the stock body roll). The rear seems in a in between SARC on/off but can go in on off mode (stiff mode). Checked the car with a full load (3 persons and full trunk), it will lose only about 1 inch. My problem it's I like my new rear sping behavior but I made some searches and I don't find progressive springs for the front of a SHO or at least a SLO. On large soft bumps, the car will dive more of the front. I want the same behavior on 4 wheels if possible. My front ones the stocks "MAD" ones with almost no rust. Thinking about that, I come to 2 solutions but I'm not a veteran so I expect that someone had more experience than me here... 1) Just put spring enforcer on the front ones giving a behavior close to a progressive spring (can I break my springs with something like that ?). I found big rubber rings (10$ each) cut in one place that can be put between 2 turns of the spring, rubber allowing some compression but with more force. 2) Rockauto sell another strong Moog spring for the front of SLO (80108). I'm wondering if someone tryed them...? Some will say that they are too weak for V8 weight but if I compare numbers from stock rear springs and cargo coil from Moog, it's let me doubtful. Let's see. Ford (MAD front springs from SHO 1996) capacity : 1107 lbs spring rate : 155 lbs/inch wire diam. : 0.56 1.26 cps (cycles per second) Ford (rear springs from SHO 1996) capacity : 567 lbs spring rate : 100 lbs/inch wire diam. (inch) : 0.50 1.34 cps Moog 80108 (front linear) capacity : 950 lbs spring rate : 169 lbs/inch wire diam. : 0.60 1.32 cps Moog rear cargo coils CC859 (progressive) capacity : 455 lbs spring rate : 137-349 (!) lbs/inch wire diam. : 0.59 (0.60 measured) 1.57 cps At first sight, these numbers let me believe that they are weaker too, going down to 567 to 455 lbs. Also found these Moog more recently. Moog rear cargo coils CC839 (progessive, but have one end different that must be cut) capacity : 426 lbs spring rate : 141-? lbs/inch wire diam. : 0.59 Spring rate and wire diameter are better on the Moog and could be a good solution maybe. The loss of total capacity on the rear didn't affect anything (height or stability). I'm wondering if they can be an ungrade or at least can be a good replacement part or the car will always be in a little "dive" position ? Also, I know that linear and progressive don't give the same behavior but my rear in hard mode can be a little stiffer and I just want same stiffness from the front end. Thanks for your help, Edit: I'm not doing any publicity, it's just the place where I found the infos.