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Discussion Starter · #1 ·
Does anyone have any pics comparing US (DOT) spec HID cutoff against a wall versus the E-code? I would imagine the E-code has a straighter line with less light above it, but I'm curious how much difference there actually is.
 

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i never knew there were two types/styles of HIDs whats the diffrence between DOT and E-code?
"E-Codes" is a term used in the U.S. to describe European-spec headlamps that lack an orange reflector. All cars in the U.S. must reflect orange from the front flanks, and project an orange forward indicator. The European-spec light projection/beam pattern is also somewhat different from the U.S.-spec. I'd assume that the U.S. is the anomaly, with the rest of the world getting essentially the same Euro-spec headlamp.
 

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Discussion Starter · #4 ·
"E-Codes" is a term used in the U.S. to describe European-spec headlamps that lack an orange reflector. All cars in the U.S. must reflect orange from the front flanks, and project an orange forward indicator. The European-spec light projection/beam pattern is also somewhat different from the U.S.-spec. I'd assume that the U.S. is the anomaly, with the rest of the world getting essentially the same Euro-spec headlamp.
The Americans didn't invent the "E-Code" term, it refers to the conformity to the ECE (Economic Commission for Europe) which regulates vehicle safety, environmental protection, energy efficiency and theft-resistance, including but not limited to automotive lighting. If a piece of equipment is compliant, it will get a stamp with an E and the number corresponding to the country code, aka the "E-Code". In Germany, for example, you will see an "E1" with a cirlce around it.

In the US we are regulated by the Federal Department of Transportation (DOT) for similar items. As you said, in the US, you must have an amber reflector at some given distance from the front corner of the vehicle (similarly you must have a red reflector at some distance from the rear corner of the vehicle).

It is however not true that the rest of the world all abide by the same standard, for many reasons (relating to which side of the road you drive on, what the height of road signs are, if they are lit, etc).

So in the US we aren't interested in just any international headlamp that doesn't have the amber reflector. We need one from a country where they drive on the right side of the road, hence most of them are sourced from Germany (E-Code 'E1').

My original question stems from the fact that I believe in Germany, all signs have accompanying lighting, so it's not necessary for the vehicles to aim any light above the 'cut-off line' in order to reflect from street signs. So if you shine an E1 headlamp at a blank wall, you will see very little light above the cut-off. This causes the aggressive multi-colored flicker effect seen on many cars with very aggressive projectors like the Honda S2000 and BMW E46. In contrast, in the U.S. a small percentage of the light still has to make it above the cut-off in order to reflect from road signs. Most manufacturers achieve this by having a slightly hazy projector lens, which gives a less aggressive cut-off and limits the multi-colored flicker.

This is a common DOT-spec cutoff line:



This is a common ECE-spec cutoff line:



The actual difference will depend on the headlamp manufacturer, so I was just trying to see if anyone had any before/after pictures of their cut-off.

Hope this answers some questions.
 

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Wow. I had no idea about all these details. Really cool.

BTW, mine should be in next week. Maybe I can shoot a photo or two for you. You'll just have to wait about 2 weeks though.
 

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good headlight lesson. Very insightful.
 

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I also recall that the sharper cut-off on "e-codes" is due tigher specs on the amount of light directed towards on-comming traffic lane.

I remember when I first moved to America from Germany looking at the cars on the freeway and seeing how there was so much light directed at you - its still that way to some extent.
 

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Anyone have some analysis on before and after A5 pics?
 

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Anyone have some analysis on before and after A5 pics?
I'm going to help ranger22 install his e-codes this weekend. I'll try to take some comparison shots of his US spec headlights (before the install) and my installed e-codes.
 

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Euro vs. US spec headlight beam spread

I helped ranger22 install his e-codes tonight. Prior to the install, we took some comparison shots of his US spec headlights and my e-codes against a wall. We really couldn't tell that much of a difference in the beam spreads when viewing them on the wall.

I'll let ranger comment on his thoughts about the e-codes after driving home with them newly installed.
 

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First off, thanks to Tx for helping me out with the ecode install. There's nothing particularly difficult about switching out these lights, but it is a tedious process.

Anyways, the pics above demonstrate that there isn't much difference when you compare the lights against the wall. From driving home after the install, it seemed to me like the ecodes are aimed slightly higher (though this might be a function of the adjustments for aiming the lights) and the beams seem to spread out more to the sides. I was surprised to notice this effect, so maybe it is my imagination. In all, I don't think the difference is drastic enough to really determine the difference between the two unless you are looking for it.
 

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Discussion Starter · #12 ·
Interesting -- I think the general trend is away from the rainbow flicker, which is too bad because most enthusiasts think it's pretty cool.

I'm on an HID/LED retrofit forum and a lot of folks go through a lot of trouble to modify thier light patterns. Attached are before/after pics of someone with an Infinity FX who swapped the lens portion of their projector with one from a Cadillac XLR. Note the colorband difference and sharper cutoff (responsible for the colorful flicker).
 

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every time I see this thread it makes me think suprablur is staring at his headlights saying things like "Give me more rainbow effect damn it! You are letting me down with the cut off line! You call that a spread?"
 

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Discussion Starter · #14 ·
every time I see this thread it makes me think suprablur is staring at his headlights saying things like "Give me more rainbow effect damn it! You are letting me down with the cut off line! You call that a spread?"
What can I say, I'm a lighting geek.
 

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Hmm... in comparison to SupraBlur's photos of the DOT spec and EEC spec lights, our UK lights are similar to the DOT light pattern (albeit, the left side is higher as we drive on the left side of the road). But out lights are meant to comply with EU regulations.

We don't have such an obvious upper cut-off line. The light does bleed up beyond the cut-off line which helps a lot for seeing unlit signs. In the UK, the only signs required to be lit by law are "terminator" speed signs. The rest normally remain unlit.
 

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Interesting -- I think the general trend is away from the rainbow flicker, which is too bad because most enthusiasts think it's pretty cool.

I'm on an HID/LED retrofit forum and a lot of folks go through a lot of trouble to modify thier light patterns. Attached are before/after pics of someone with an Infinity FX who swapped the lens portion of their projector with one from a Cadillac XLR. Note the colorband difference and sharper cutoff (responsible for the colorful flicker).
Sorry to revive this thread, but yes, I was curious about how the levelling would appear drivers vs. passenger side. For my S2000 the HID's also have this "prism" optic cutoff... It's nice. But also the light arc is slightly more wedged, and supposedly this is to accommodate oncoming traffic (or so I heard). So I wondering if the E-code lights were inverted... I guess not. Very helpful thread!
 
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