S14: Popping noise during slow turns

[chituntang]

It starts to make this popping noise recently. This happens when I am driving really slow (almost rolling speed). It happens to both left and right side. I have done the following things to the front suspension:

New OE struts tops with KYB AGX and RSR springs
New Moog FLCA ball joints

I am planning to do the following:
Rebuild power steering rack
Tension rods

Thanks in advance
Jesse

BTW, does anybody knows if a fully loaded IS350 (I mean fully loaded like NAVI, heat/cold seats, like everything) has stock bigger wheels at the back? Looked at one today and:

Stretch tires running 225/40/18 front and back
Passenger front wheel has a dent

Any of the above would cause shaking? I am not talking about the steering wheel, but the ride is shaky. The steering seems fine.