I have been obsessing about Hella 128's for some time as i tried and find what is correct for my 65 911 (1022). I guess it started when I bought a nice NOS pair thinking they would solve my problems but they only started them when research confirmed they were upside down and not for Porsche. There are various threads here and on the early 911 registry that provide some info but not one thread that clearly defines everything - which would be hard because when you get into it there are multiple changes depending on market and age - and of course these were fitted to other cars such as Mercedes BMW and sold at the corner auto parts store as accessories.
Here are some thoughts I have based upon research, what I have collected or seen online in the last 18 months.
BULBS/REFLECTORS:
1)Tungsten 35w- up to '68. bayonet bulb fitting with large bulb cover about 1 1/4" There are early and late bulb holders - early reinforced bakelite, later steel.
2)Halogen 55w - from '68 square bulb mount slot & clip, small bulb cover 3/4" All reproductions are halogen - although the reflectors are interchangeable.
3) Tinted yellow to go with clear lenses some versions - rare.
HOUSINGS:
Drain Holes
1)Triangle by mounting bolt - for mounting "upright" bolt facing down. Not for Porsche application - an accessory or for other cars. 99% of what you find in Europe, not so common US.
2)Triangle opposite mounting bolt the one we want for Porsche - for mounting "upside down/under bumper bolt facing up drain facing down. Hard to find!
3)Slot in bezel/none in housing. - Introduced about 1968 when the V was removed. Also at this time a notch appeared in the bezel that lined up with a ridge in the non V lense. This design makes the housings universal right side or upside down mounting. No reproductions have aforementioned triangle drain holes.
Bezel Mounting
1)Full ring spot welded - as per 1957 NOS
2)Full ring one rivet each side - why?
3)Clips each side spot welded - as per Jims original '65 - the housing pressing changed for this.
4)Clips each side riveted - two rivets From '68 - I'd say cheaper to manufacture than polishing spot welds and no deformed housing if screws overtightened. Aforementioned is likely evolution. All reproductions have the two rivets each side.
Material
'57 (full bezel mounting ring) are steel.
Others are brass. (cenetr earth tab/rivet)
Earth tab
The tungsten versions had an earth clip riveted inside the housing. On the the '57 lights this is riveted to the mounting plate. The others I have this is single rivet in the center opposite the mounting bolt. One set I have seen has later slotted bezels and the center rivet.
Some early housings have "Hella 66893" stamped by the mounting bolt - not common.
BEZELS:
1)Plain. Correct for Porsche up to '68
2)Slot for drain & notch. Correct for Porsche from '68
3)Hella Logo raised on top - does not appear on early Porsche 911 brochure. Most used original from Europe have this. I think its really cool - my two sets of 57 date stamped have it. Maybe its an early thing?Easily removed if rechroming...These bezels also have n=25cm/5m stamped in.
LENSES:
Where do you start?
1)Yellow = Europe. Clear = US. Seen plenty of clear ones in Europe. All versions of lenses seem to come in both colors.
2)Yellow coated glass inside - can be removed to make clear - original? Yellow tinted glass - reproduction?
My theory is that that as the lenses evolved more script/compliance codes were added.
1) '57. Early Hella logo (In 1958 Hella changed their logo. The H of Hella formerly enclosed to the left changed to open. The later logo is flat on the ends and taller, the the early is oval on ends). There is squiggle /\/\/\/ at the base of the V - (German compliance?) Only other script is 3/32" tall and hard to find read - OBEN at top 66893 at bottom. NOTHING else!
2) Next reference I have is 1965 911 brochure. This has what I call the crown logo - I have seeen two versions. As expected the Hella logo is now open by the H. By this time more of the script we see on later lenses has arrived: Made In Germany. A. 66893 large script.n=25cm/5m.
3) More compliance script got added around the perimeter: IGM2042PM. SAE F64. /\/\/\ K1112. 11-60893. Don't know the timing but I have seen various combinations of some all. Obviously open H Hella logo. The current reproductions have everything but without n=25cm/5m.
4) 1968! For some reason the V was done away and straight bar introduced along with the many changes made as mentioned above notably halogen bulbs and two rivets on sides. Within a couple of years the V was back in the parts books so you got all the changes with V lenses - this being the last of the evolution appears to be what todays reproductions are based on. There are some some excellent quality out there and they are really the only practical solution. Are they totally correct for a 356 or pre '68 911..... not really (although most are not as anal as me)
It took me more than a year to find the parts for what I believe to be correct for my 65. I have to tool up to do the rivets, remove dents, rechrome, replate mounting bolts resilver reflectors. By the time I count my time it'll be 5-10 times the repros.
So to conclude there are perhaps something like 8/10 versions of lenses, 8 versions of housings, 3 or 4 versions of bezels.
PHEW - confused yet.
Any input confirming or denying particulary with reference to date codes on the reflectors really appreciated. Guess it needs its own thread with pictures and tables - maybe one day
