Tried searching but couldn't find anything specific with these coilovers on this car. Had HSD HR coilovers installed on my 2007 G35S a few weeks back. They started making a popping/knocking sound after a few days from the both front struts so i snugged up the top bolts a little with an impact. Didn't get crazy with it just gave em a few shots. Still made the sound. Added about 30mm of preload to the front springs (too much i think) to just eliminate that variable. Still makes the sound. Took it back to the shop I got them installed at and the mechanic tightened up the front nuts some more. Now the sound is even worse and it makes it over the smallest imperfections at low speed and when turning the wheel. I'm now leaning towards maybe the top nut being too tight and possibly binding up the top bearing from letting the assembly rotate when hitting bumps or turning hence the noise from the spring seating/unseating. Do you guys think that this could be the cause? Going to try to back off the preload tonight and maybe loosen up the top nut and grease the spring perches. Any help would be greatly appreciated as I'm pretty much at my wits end with this. Thanks in advance.