Between installing the springs and the alignment happened I noticed the car would hop around alot in the rear without the rain. In the rain it was undriveable. The alignment shop checked the alignment again after 3000 miles and was ok. After an alignment it was 90% improved however I notice the cars rear end shifting about still but just a little after hitting almost any bump on the interstate at almost any speed. I just bought new tires because I needed to and thought that may help, it didn't. I do have the camber aligning lower arms and I didn't need to slot the chassis since alignment shop said it was in spec.
I have had stiffer cars even lower and not this kind of slight shifting going on. I still have the OE shocks.

Question: Does anyone have this slight shifting or dancing in the rain over almost any bumps on the interstate? Or is my rear alignment still too much toe in? No toe in rear jokes ok?

 

I cannot speak for the Toe being and issue or not but I know when I did not have enough camber in (I was just eyeing it for a week until I could get in for an alignment) the back end would "slightly shift" when I hit bumps. Once I put more camber in that went away.

 

Do you have your sway bars set at their stiffest setting? Either that or something is binding up in the rear preventing suspension articulation.

 

I wish. Stock bars.

 

My guess is toe out/in. Do your tires screech when riding over the painted lines on a street or making a slow turn.

 

if it is hopping and you still have OEM shocks, its possible that the shocks are done. If you lower the car on stock shocks that already have years of wear on them they can blow out sooner than they would otherwise. Just another thought

 

I have heard this but never heard of this actually happening to anyone. I have done this before without these results. Stock shocks and stiffer springs *should* not cause this. Has anyone experienced this?

 

Could tramlining be a factor here? Did you go to new wider tires by chance during these other changes?

 

I put on 235/50/17. The car does it everywhere. I am convinced I need shocks, and better than stock! :-) I am biased as I could literally feel 1psi difference in rear tire pressure upon acceleration in my BMtroubleUs. They were tweaked though. Butt dyno is pretty accurate.

 

keep us posted. I plan to run Eibachs on stock shocks too and I want to make sure the car is driveable. I also plan to run wider tires on a square setup

 

I will. My shocks have 98k on them and the car is driveable I just don't know how it will drive in the snow yet. It will be a long time before I get shocks and I may remove them and install Teins - used/cheap.

 

My car did this bad when I was on stock shocks to the point where I decided to spend the money on some BC coils. The adjustability of the shock dampening helped a lot but I have 370z 19's and I tramline pretty bad. I have an spc rear camber kit but nothing in the front. I'm about to upgrade my control arms to see if that will help with some camber adjustment up front. Something else I'm considering is tie rods being worn, I'm at approximately the same mileage as you and it's something where if they're upgraded with better parts it can only be that much tighter.

 

Alignment was all fubared in the rear. I caved and took it to the local Dryer and Reinbold in Indy and they actually came through for me. I had trans flash and four wheel alignment for $160. Not bad and I may not bad mouth them until they **** me off again. The Infiniti alignment guy went to the D&R BMW dealer next door to do the alignment as they are small in SF. He actually called me on the service guys phone and asked me what I wanted and how I wanted it. Then after it was done sat with me for 20 min to explain that my rear needs another .38-.5" in increased height to get the toe in correctly. I will probably get a really large split washer made (.38-.5") for the bottom of the spring.

 

Do you have the rear camber arm & toe bolt kit? If not that WILL get your alignment proper. On an Eibach drop you'll only need the 4 bolt kit, costs about $50.
http://www.spcalignment.com/componen...AFrom&to=USATo
Install info
http://www.spcalignment.com/instruct...65-INS_WEB.pdf
And vendor
SPC Performance Camber/Toe Cam Bolt Kit; Pair, Reqr's 1 per Wheel INFINITI FX35

 

Glad to know it was just an alignment issue. All in all that is a pretty easy fix. I will continue to head in that direction then.

Hey BLNewt, those are for the G35. Thats not the same is it?