Originally Posted by planman

Dirtman has some really good info here.

I'd contribute an example:

With flat flares and minimal trimming of the rear fender well pinch seam, 35" tires can be run on 4.5" or less backspaced wheels with stock front bumpstops and about 2" rear extended bumpstops. So, you could run shocks that measure up to about 15" collapsed in the front and about 17.5" collapsed in the rear without bottoming them out. To gain more than stock articulation (flex), you'd run as long a shock as your springs would permit, as long as the collapsed length of the shock was at or less than the 15"/17.5".

With the same flat flares and rear pinch seam trimming, 37" tires can be run with 1.25" front and 2.5" rear extended bumpstops.

So, as an example for someone wanting more articulation (flex) with a mild lift of 2.5"-3":

You can run OME 11.5" travel shocks (16" collapsed and 27.5" extended) with 1.25" front extended bumpstops and longer front brakelines--and longer front swaybar links if you run them off road with a Rubi disconnect system.

You can run EVO RockStar (or similar) rear skids/shock relocation brackets that raise the rear lower shock and swaybar link mounting points about 1.5" with 11.5" travel OME shocks (16.5" collapsed and 28" extended), 2.5" rear extended bumpstops, longer brakelines, and longer swaybar links.

With this setup, you would need springs that can handle 11.5" travel without unseating. The rear coils would need lower coil retainers. OME HD springs can handle it. Metalcloak and Rock Krawler 2.5" springs should be able to handle it.

With 11.5" travel at the shock, you will want a flex joint (spherical joint) at atleast one end of at least the lower control arms. The front axle side upper control arm bushings in the axle will last longer if the front upper arms have a joint at the frame side instead of a bushing.

That setup, with appropriate adjustable trackbars, will RTI 1000 on a 2 dr JK with close to stock wheelbase.

The setup significantly increases articulation (flex) over stock because the combination of shock lengths and rear mounting points, extended bumpstops, longer brakelines, longer swaybar links, longer uncompressed spring lengths, etc. allows the full use of 11.5" travel shocks.

I haven't ever measured the actual usable shock travel with the stock setup, but I would be surprised if more than 7"-8" shock travel is useable.

Originally Posted by Jeeepr

Great write up, I learned a lot about lift from this thread. I still want to add about 2.5 to 3.5 on my 2 door to make way for 33's or 35's. One thing I still had questions on was the factory suspension vs a lifted or modified suspension, IE the factory control arms and etc vs upgraded ones you get with many of the kits out there today. My thought was if your going to be doing any off roading wouldn't the upgrades from a lift kit be a good idea? Better bushings, stronger control arms, better shocks and springs from a lift kit vs the factory versions.

Originally Posted by planman

The stock springs are fine until you start adding really heavy bumpers and armor. As a result, a 2.5" BB with 10" travel shocks can work very well for people running 35s with stock flares and who want to prioritize funds for regearing and drivetrain upgrades.

Originally Posted by planman

The stock control arms are good for up to about 10" travel shocks with up to a 2.5" lift and the kinds of off roading most people do with 33s or 35s. The stock springs are fine until you start adding really heavy bumpers and armor. As a result, a 2.5" BB with 10" travel shocks can work very well for people running 35s with stock flares and who want to prioritize funds for regearing and drivetrain upgrades.

Originally Posted by Denton

This is a great thread. Has me rethinking the direction I want to go with my rig.