by Desert Dog » March 15th, 2011, 7:13 pm
[quote="RyanSBCA"] I just got a 1 3/4" spring spacer lift to hold me over until I pull the trigger on a full suspension LA Lift. [/quote]
Like Abendx said, there is a 90% chance that a long arm kit would be a big waste of money for your JK. Don't listen to the TJ and YJ guys when it comes to JK lifts - with a 3" lift and fenders, you can run 38s if you had the axle strength to do it. The JKs come from the factory with pretty long arms and lots of room under those plastic fenders.
As someone who has ran my rig with long arms and short arms I can tell you the difference: with a 4" short arm lift and 37" tires, my Jeep worked perfect. Performed great off-road and rode like a dream on the highway. Then I went to 39.5" tires and added 1" pucks for a little more up-travel. After that, my jeep rode a little worse and felt a little less stable. I was preparing to run coilovers and knew I was going to get a little more axle droop than before, so decided to change to a long arm kit.
The control arms need to sit as parallel to the ground as possible to get a good, stable ride on the street. For the JK, I found that the 5"-5.5" mark is where the angle of the arms get extreme enough to feel the difference. Moving the arms further back on the frame (increasing the length) brings the angles closer to the stock geometry. This allows the axle to articulate in less of an arc. But contrary to popular belief, long JK arms don't give any more flex than a good short arm kit and the difference is not noticed until over 5" on a 2-door.
If you are running lift to run 37" tires or less, the long arms have more negatives than positives; you lose ground clearance, cost is double and installation complex and expensive, and your jeep can never be returned to stock.
I AM THE TITTY MASTER