i might be picking up some ctr headlights off a friend and he said they are "rhd headlights for japan, uk, australia and stuff." is there a differnece with the usdm oem headlights? if so can someone explain the difference please thanks!

 

The colour of the headlights. That's about it.

 

so rhd and lhd headlights all the same?

 

Fitment yes. Look no.

 

The part numbers for headlight assemblies in countries with RHD are completely different from countries with LHD. I believe they are designed to be focused on a different part of the road so as not to blind oncoming drivers - other than that they are the same. Now, whether you can adjust your RHD headlight unit to compensate for this, I really don't know .... but I definitely wouldn't drive with them as-is. You do NOT want blinded drivers coming at you -- that is a recipe for a crash, and probably right into your own car.

 

Correct me if im wrong but on Nissan JDM lights the beam shines to the left and on USDM Lights the beam shines right. This is done to keep glare out of the eyes of on coming traffic. Which it could be a nissan thing or not true at all.

 

X2

 

yeah i heard of this somewhere too.

 

theres a dial on the back of the headlight to adjust. and you can always undu the bolts on the top and (by milimeter) adjust it

 

I always hear that, but I never see any actual evidence. I've driven plenty of LHD cars, and if the headlight alignment is normal, it doesn't seem like the beam pattern is angled anywhere in particular, it just goes straight. Most headlights I've seen (EF headlights for sure) let you adjust the angle of each one independently, so I suppose they could be changed/customized any way you want, perhaps to lower the beam on the side that's close to oncoming traffic. I've never driven a RHD car, but are people trying to say that for some reason those have an angled beam pattern? or are LHD cars supposed to be like that too?

I remember someone showed this photo to say "see! RHD cars cast a beam to the left!".....but the careful observer will note that if you stood on the opposite side of the same car, the beam pattern would be going in that direction. Try it yourself if you don't believe me...



If you stand on a wet surface, the pattern of the beam will always go towards you. Furthermore, every car I've driven has a ~170º angle of light that's pointed straight forward--I've never seen one where the angle was shifted to the side.

 

Its the beam pattern... typically this is on old headlights only... when i say beam pattern im talking about the lines on the headlight lense and housing... it directs light in certain directions... and yes they are very different. that dial in the back of the headlights only adjusts height.

 

This is a good discussion. 90Rexx makes a good point - the fresnel lines on the lens probably make up a lot of the difference. However, at least on 5th Gen Civics, there are two dials to adjust the lights: up/down and left/right... I doubt, however, that you could turn it enough to compensate.... but I might be wrong.

Here in Canada, where we can import any vehicle from any foreign market, RHD or LHD, that is 15yrs or older - one of the stipulations for making the vehicle road-worthy is dealing with the headlights. I'd have to research this to figure out what exactly is required.

I agree with hushypushy that whatever "test" that person did to "verify" the difference between RHD and LHD headlights is about as scientific as reading the bible, then pointing to it and saying "See? Humans did not evolve from monkeys." The photo instead shows simple Grade 12 physics at work: angle of incidence = angle of reflection. At least a comparison from the other side of the vehicle would be in order.

 

Yeah, I'd like to know what the headlight requirements are. I think you may even have to change the headlights when you take a Canadian car to the US. I know one thing is that we have to have reflectors in the headlights over here, I don't know if that's the rule in Canada as well. But that doesn't have anything to do with the beam, of course...

 

yea, i see what you're saying. its like those pics from the moon landing that people said were fake because not all the shadows were going in the same direction, and therefore their must have been 2 light sources. anyone who understand how the angle of a given plane changes the perceived direction that a light is being cast, knows why this makes no sense at all.

as far as whether there is a big difference with beam pattern between lhd and rhd halogen headlamps i imagine they are probably not, but i'm not one to say.. the only case i know without a doubt that the beam would be different is on some vehicles with projectors from the factory. some have a cut off line on the right side which shoots up at like a 45 degree angle. presumably to better illuminate street signs, and stupid deer that might decide to commit suicide that day.

 

Another thought: JDM headlights, at least for the 5th Gen Civic, use the H4H bulb, not a regular H4 as in CDM/USDM/EDM. H4H bulbs cost $$$ AFAIK, though there are ways around it.

 

To make it a little easier, the cutoff is all that is different for LHD vs. RHD headlights.

In the US, headlights pointed at a wall with the car on flat ground present as:
___/-----

And RHD lights are the opposite:
----\____

This is why people say they "aim to the left". They don't actually aim to the left, but they do allow light to be projected higher up on the left side. This causes glare for oncoming traffic, and makes RHD headlights in the US a hazard for other drivers.

Yes, you can aim headlights up and down, but you can't change the cutoff without modifying the optics. To be less unsafe to other drivers with RHD lights in a LHD country, aim them down slightly more than normal.

 

THis is actually the reason i didnt go for the JDM head lights. I actually shopped around for a couple of month till i found a set or EDM head lights.