AC White Paper: Top Three Vintage Porsche Headlights

Top Three Vintage Porsche Headlights


The Top Three: Cibié Bi-Iodes, used on Porsche production 9111R's, 911ST's and 911RSR's, are the most sought after headlights from this era, but the Bosch H1's and the SEV Marchal Amplilux's are equally cool in my opinion.

It's interesting that the coolest headlights ever used on Porsches were over 50 years ago during the brief H1 halogen bulb era. It was due to a clever adaptation to a serious limitation.

It must have been exciting when the H1 halogen bulb was first introduced. At that time the choice in the U.S. was sealed beams. The rest of the world (RoW) did a little better with reflector headlights using dual filament 40/45w tungsten bulbs (these were the fore-runners of the H4 headlight). Nothing very impressive in what could be called the automotive dark ages (sorry) compared to today.

The new halogen bulbs were great but there was one big problem - they only had one filament so how could it be used in automobiles that had two beams. The three headlights featured in these white papers all used the same clever solution - two reflectors and two bulbs.

If you're fortunate enough to come across a set of any of these we would enjoy restoring them for you.

Cibié Bi-Iode Headlights

A Rare and Beautiful Headlight for Early Porsches

The 7" Cibie Bi-Iode assemblies were an upgrade to sealed beam lights that installed directly into the Hella sealed beam housings, replacing the sealed beam unit. The dual bulb, dual reflector Cibie Bi-Iodes, used on the Porsche 911R, 911ST and 911RSR (Ford also used them in the Escort MK1), are perhaps the rarest and most desirable headlights for early Porsches.

Cibie Bi-Iodes, similar to Bosch H1 headlights, used two H1 bulbs, a higher wattage bulb for the high beam and a lower wattage bulb for the low beam.

In addition to being used on the Porsches listed, Cibie Bi-Iodes were also used on the Ford MK1 rally car. It's usually easy to tell by the condition of the lenses where they were originally used as on the Porsches they were mounted behind the Hella lens in front and so had very little wear while on the MK1 there was no protective lens in front and they usually show road wear, such as sand blasting.

Some versions included an extra hole in the large reflector for a  city light, a 4 or 5 watt bulb often required in headlights in Europe. Other versions had no provision for a city light.

Here's a picture of a disassembled one. The bottom reflector was attached in an ingenious fashion using a leaf spring (pictured under the large reflector) to provide tension on the small reflector. 

The opening for the bulb holders and the bulb holders were covered by rubber, with the shape varying from time to time.

There are at least two versions of lenses and there's a debate as to whether it's Ok to mix and match them. Here's a point of view from automotive lighting expert and AC consultant Daniel Stern:

The 7" Biodes were not homologated for low beam in either LHT (editors note: Stern uses the terminology "LHT for Left Hand Traffic" as he feels it's more accurate than LHD, Left Hand Drive) RHT versions. Also, the hot setup for any kind of a track or road race or rallye car in that era was a LHT lamp on the left side of the car and a RHT lamp on the right, for much better LH and RH curve and bend light on low beam. The non-homologated low beams have very much less height to the nearside upsweep, so even with proper (not artificially low) aim there will not be unsafe or illegal levels of glare or dazzle to other drivers.

 Other Applications

Other than early Porsches, Cibie Bi-Iodes were produced for other other marques, including Citroen and Peugeot. These are a bit larger than the assemblies used by Porsche, measuring 190mm in diameter vs. 170mm in diameter. Those are much more common than the 170mm version and much less expensive. Audette Collection has engineered a design enabling them to be installed in the Hella SB19 headlight buckets.




 The term H1 actually more correctly refers to a type of halogen bulb, but over time in the Porsche world it has come to stand for the headlamp assemblies made by Bosch that use two H1 bulbs. The following information has been gathered from my experience with these fascinating devices and from informative discussions on the Early 911S Registry and other research - and experience restoring them.

Telling the difference between H1’s and H4’s

It’s easy to identify H1’s vs. H4’s when you know what you’re looking for:

History of Bosch H1's

Here are some historic facts in no particular order:

  • The first halogen bulb for vehicle headlamp use, the H1, was introduced in 1962 by a European consortium of bulb and headlamp makers.
  • H1’s were first offered as a factory option for the 1968 911S beginning with chassis 11800226 (coupes) and 11850065 (Targas) and additionally for 911T’s and 911E’s starting in 1969 (from posts by Registry members citing Bosch and Porsche publications). They were available as after-market add-ons beginning with their introduction in 1966.
  • H1’s didn’t become legal in the U.S. Until 1997 !
  • There was one generation, or model, of early H1’s made with city lights in the buckets. These appear to be uncommon.
  • The first LHD lenses were marked …007 with raised letters on the outside of the lens and had a larger prism, with two bars on the top of the prism (1966-1969).
  • The next generation of LHD lenses were marked …010 with raised letters on the outside of the lens and had a smaller prism with one bar at the top of the prism (1969-1972). There is definitive evidence that the raised script lenses were used at least into 1972. Source: Owner of Porsce Parade Concours Trophy winning 1972 911S.
  • The subsequent, and current, generation of LHD lenses are marked …010 with raised letters on the inside of the lens (1973-present)
  • H1’s were made for and used on early VW’s. The chrome trim ring has the mounting tab at the 6:00 position and they had the small bulb “city lights”.
  • There are two versions of the low beam bulb holders, probably a generational change.

Information on AC Restoration Services for Bosch H1 Headlights


SEV Marchal Amplilux Headlights

SEV Marchal Amplilux

The SEV Marchal Amplilux were 7″ assemblies that fit into the Hella sealed beam housings with no modification. Used to replace the poor performing sealed beam headlight, the dual bulb, dual reflector Ampliluxes dramatically increased the performance over sealed beams and are, second only to the Cibie Bi-Iodes, the rarest and most desirable of headlights for early Porsches equipped with Hella sealed beam housings. Like the Bosch H1 and Cibie Bi-Iodes, they were a work around designed to enable the newly introduced halogen bulbs to be used in automotive headlights. Halogen bulbs at that time had only one filament so in order to use them in cars where two beams were required it was necessary to have two bulbs – and hence two reflectors.

Bulb Arrangement & Performance

The top reflector (upper half) was fitted with an H1 bulb and used for the low beam. The bottom reflector was fitted with an H3 bulb and used for the high beam. Ampliluxes, like the Bosch H1 headlight and the Cibie Bi-Iode headlight were complex and expensive to manufacture but they were the only way to use the advanced halogen bulb in automotive headlights until the two filament H4 halogen bulb was introduced in 1972.

The Ampliluxes had a sharp low beam cut-off and a far reaching high beam that could be adjusted separately from the low beam, creating an almost laser like far reaching beam.

Photo showing Amplilux's mounted in the Hella housing used for sealed beams. You can also see a decal with instructions for installing the H1 and H3 bulbs.

An Amplilux headlamp installed on an early longhood. They fit into the Hella sealed beam housing with no modifications required.


Other Versions

Please note that there were two versions made and only one version was used on Porsches. The other version was used on Citroens and Peugeots. The ones pictured here have the correct high beam reflectors for Porsches. The incorrect ones have a far different shaped reflector and have a much lower value (see picture).

I believe that these are the most under-rated of the three headlights that we feature in this series. They are much more rare than Bosch H1's, probably equivalent to Cibies. And an interesting aspect about the performance of Ampliluxes is that they provide a very unique low beam cut-off and a super intense, far reaching, pencil like high beam that is not easily duplicated in a single bulb light assembly. You might want to keep your eye out for a good set of these. Condition doesn't really matter, other than the lenses which are usually in good shape, as we can restore them for you.