Originally Posted by KonaBlueKiller View Post
OK so I'll try to explain as well as I can. The only rear mods that I have right now are the j&m control arms and K springs. I had my nitto 315/35/20 nt05s for a few months now with some track passes on them but no real crazy antics because they are pretty big and sticky. Its had some damn hard launches though. Everything seemed fine and then I installed my K springs last week. It seems to sit lower than it should and the bump stops are literally touching where they bottom out. Just lightly... They are also angled back like the rear end is clocked back about 5-8°… This doesn't seem normal to me. The bottom control arm bolts are tight and I haven't installed my steeda relocation brackets yet so the control arms are in the stock location. Didn't have a good chance to look but the UCA seems OK but need to check better when I get home (I'm offshore). Also when I get into power and let off or go from reverse-forward-reverse the rear seems to move slightly on the right side. When you're going 70-80 the car actually shifts slightly when on and off the power. The day after I lowered it my buddy did do a pretty hard donut in it before I got a chance to say not to (he's not driving it again). Can you bend the UCA or its mount if its stock? Also people who put on k springs are your bump stops straight up and down or are they cocked back a few degrees contacting the angled part of the bump stop touch point?
Did you install an adjustable panhard bar?
I wouldnt worry too much about the position of the bump stops. If your LCA are the same length as the factory, and all of your bushings are on "ok" shape, you are fine. Lowering the car slightly is not going to twist the axle enough to make a negative impact on the position of it. I DO RECOMMEND an adjustable upper arm though, for a few reasons.
Typically, when a car shifts at higher speed, it is due to the bushings, or occasionally a misalignment of the rear axle.
Check all of your bushings. The factory bushing in the differential, (the bushing attached to the housing) is prone to premature failure when abusing them, or, driving hard.
Check your bushings.
Install an adjustable panhard bar, if you don't have one, and adjust it.
Cut 3/4" to 1" off of your bumpstops.