I have heard good things about the Illumina and H&R setup however I would like to know whether this setup is going to give a smooth ride, and make the ride on rough ground fairly smooth with 18 inch rims and 235/40/18 inch tires? ANybody have any personal experience. I really do not want to drive around anymore with the constant bumpiness I have right now with stock struts and drop zone springs (2 inch drop), but I would rather not waste the money if this setup will not give me what I am looking for. Instead I will sell my 18s and get so 16's instead.

 

I have em on 16's. I have motivational strut mounts as well....it is a smooth ride, soaks up small imperfections in the road, but I still avoid manhole covers, potholes etc.. the bigger the rim diameter the harshness of the ride is multiplied

 

well I just want to know how bad it really is. I have road in a max with 17's and agx/eibach, and thats a pretty harsh setup in my opinion. I am looking for something that will absorb more imperfections then that, and I couldn't care less about handling.

 

18's will impact on bumps harder, but the overall ride on the highway should be very smooth.

I bet if you coupled Eibach springs with the Illuminas the ride would still be very smooth and the handling would be insane. H&R's and Eibach's almost ride the same on the highway. Eibachs impact is felt on bumps more as H&R's have slightly more give to them, helping your car absorb bumps better. Both springs, IMHO handle excellent!

 

would dropping down to a 17 inch rim or even 16 inch rim improve the smooth ride tremendously with H&R/illumina setup? What I don't understand is how cars like mercedes 500 SL, or the 740i BMW's drives so smooth, and absorb imperfections so well, despite the fact they have 18's.

 

Well, it probably cost Mercedes and BMW millions of dollars for their engineers to tune the suspension and tires for that perfect ride while maintaining that great handling! Unfortunately without knowing the particular suspension characteristics, our efforts are limited to hit and miss unless you have a budget that allows you to try several combinations of parts. Experiment along and enjoy the experience!