I've successfully retrofitted HID into the W210, as have a number of others. We pooled our experiences on MBWorld and have basically used the following (in a nutshell)....
- Depo projector based H7 headlight ($250-400 pair)
- D2S Philips/Osram 81522 bulbs ($100 pair)
- OE ballast (Hella, Denso, Mitsubishi... $2-300 pair)
- E55 or RS6 bixenon projectors
the sequence is roughly as follows.....
1 - remove all removable parts from Depo 2 - heat oven to 250=BAF - turn off 3 - place Depo inside for 10+ mins to soften lens adhesive 4 - remove large outer lens 5 - remove Depo projector and toss in garbage 6 - mount HID E55 bixenon projector to Depo (minor fitting involved) 7 - splice bixenon solenoid to high bem leads 8 - reheat oven to 250=BA and insert Depo to soften adhesive; reattach outer lens seal outer lens with RTV silicone 9 - reattach all small parts into Depo 10 - relieve back cover for high tension ballast lead 11 - install inline fuses to ballast input leads 12 - connect all wiring, mount ballastGoing the HID kit route is dangerous to other drivers as it nearly always results in uncontrolled glare. The kit is rarely calibrated to the projector or reflector the owner has on their car. It is an inexpensive one- size-fits-all answer for the vendor and those too cheap to care about beam quality.
Though technically not legal, the above described retrofit uses bona fide HID calibrated projector, bulbs and ballasts....and simply retrofits them into the Depo housing. The results will put a smile on your face.
aesthetics, before/after
Total labor time can be as little as 48 hrs, though my first retrofit took at least 3 weeks
I do this for fun and dont take orders so do not email me, but I am happy to help give you tips on your own installation/retrofit. Note that another person on MBWorld and Benzworld boards does take orders so you can search and ask him.
The overall cost is 2-3x that of HID kits but quality of lighting is
200x+ better....and rivals OE lighting in quality (natch, since we're most using factory parts). This retrofit is about 1/2 the cost of OE....but note that MB does not make projector based lighting system for W210s. You will not have autolevel feature found on factory HID MBs so you should aim your light a scootch low to minimize impact to opposing drivers.raymond- avi8tor01 at yahoo dot com or waltermitty01 at juno dot com