[1] 190E 2.3 (also 190D USA models)

Front: 0.87" (22mm); factory
Rear: 0.51" (13mm); factory

source: AMG Technical Guide

[2] 190E 2.3-16V
Front: 0.91" (23.2mm)

source: just now measured them with Mitutoyo digital calipers. I'm waiting for rental spring compressors to arrive so I can install H&R sport springs and Bilstein sport shocks -- that's why the sway bar is removed. Also installing new bushings which I just picked up today.

Hope this helps.

Brian16V