I've been looking online at a bunch of different brands of lift kits and haven't found a single one that says what the spring rate for the springs is or actual height gain. I found a formula for figuring approximate spring sag depending on how much weight you add but it only works if you have the spring rate and know how much weight you're gonna be adding. I am going to be adding about 200 in the front and 250ish in the rear. So does anyone know spring rates for the "big name brand" lift springs? I am going to be running 35" Mickey Thompson Baja MTZ's or ATZ's havent quite decided yet but both have an actual height of 34.4" which is pretty close to an actual 35 and want to make sure that 3-3.5" lift will still fit the tires without rubbing when I go off road. I don't do really tough trails but I have stuffed my stock tires into the front fenders a couple of times and I have a 2dr Rubicon that has 4dr Rubicon Springs on it so I want to make sure that it don't happen after I get a lift and new tires on it.
I can check back once a day or so and can post anything else that's needed.

 

They vary in the 300-330 pound rate but you are right in that nobody list them and don't expect them too. Most are built to give you the lift advertised with steel bumpers, armor and winch so they sit high. Its typical to get 4"+ from a 3.5" lift on a stock vehicle. A 2" lift is plenty for 35" tires. Bump stop and proper wheel back spacing prevents rubbing not lift size.

 

I know that the wheel backspacing makes it so you can turn lock to lock without rubbing but if bump stops are supposed to keep your tires from going too high into the wheel well and contacting the fender would an extension on them help since I have managed to get the stock tires on stock rims to rub on the upper inside of the wheel wells? New to wranglers, used to trucks and ZJ's which are different beasts.

 

Yes, simply add some bump stop.

 

Did some research back in a day, when I shopped for springs for my JKUR. Dont remember all the details anymore, but the only company, who manufactured springs with rates close to stock, was Eibach US = you may want to check the springs they include in their all-terrain lift kit. They sell them separately too. Rode those for 2 years and was very happy with the handling. However after adding winch, double batt., HD rockrails, etc. I had to swap them for AEV, as the sagged.

 

How do you like the AEVs? I already have new bumpers waiting for me at home along with some skids waiting to be bolted on, so I think the Eibachs would sag either quickly or right away, so I know I need something stiffer than factory

 

Old Man Emu has different coils for different weights you might want to look into those if you are building a heavy although the weights you listed in the op are not heavy and I would not be concerned with sag if thats all you are adding.200 pounds added on most coils is only going to compress about 1/4-3/8"