I have a set of US X5 projectors on my retrofit, they have harmonized cut-off lines or the "Z" cut-off lines. And I've been wondering how are the "Zs" supposed to be aimed, I've searched through the FAQ and still couldn't find the right answer.



1. The lower line of the "Z" is where you aim in terms of the cut-off, right?

2. Should the "Zs" even meet after a certain distance?

3. I've notice that if one of the "Z" is closer to the center and the other one isn't, to the driver directly in front of you, he or she may feel that one side is aimed higher than the other because of the raised part of the "Z"

4. Help!

1. yes
2. No, beams are supposed to be paralell. From the drivers seat, at longer distances (over ~40meters), its impossible to see what light is coming from each headlamp.
3. the higher part of the z should not be high enough that it would raise a concern, unless application is a halogen fixture retrofit.

Herman, if I aim the lower horizontal as per the guidelines of 2.1" drop per 25 feet, I end up having the upper horizontal in a nearly upslope, are you sure about taking the lower horizontal for the standard drop?

You aim vertically from the LOWER (leftmost) horizontal cutoff. You aim horizontally straight ahead, with the distance between the LOWER "V" points equaling the center-to center distance of the headlight lenses. The lower horizontal cutoff on both lights is to be parallel to the ground and to each other.

Right, but like I said if you aim the 2.1inch drop per 25 ft on the lower horizontal, then the higher horizontal is no longer in a downslope. Is this right?

Al wrote, "Right, but like I said if you aim the 2.1inch drop per 25 ft on the lower horizontal, then the higher horizontal is no longer in a downslope. Is this right?"

I don't understand the question; changing the aim will not affect the beam pattern built into the headlight.

Ekooke:

"You aim horizontally straight ahead, with the distance between the LOWER "V" points equaling the center-to center distance of the headlight lenses."

I really don't understand what you're trying to say, where are the "V" points? and can you maybe elaborate a little more on what you were saying?

Thank you

Look at the drawing on the top of this thread. Follow the left-most horizontal line to where it starts to rise at an angle. That's the notch of one "V", with the other "V" being on the other headlight beam. The lights should be aimed horizontal straight ahead with the headlight center-to-center distance matching the distance between the actual, physical headlight centers. Maybe this light aiming instruction is a little clearer than the other one already posted:
http://www.autooptiks.com/aiming.html

Tom,

no, if you aim the lights as described, the right-hand portion of the z-pattern will not go up at an angle, only down at a lesser angle. This is merely extra light to help you see a little better.

Geepherder and Ekooke, that's exactly the point. In order to have the upper horizontal in a downslope, I must aim the lower horizontal more than the prescribed 2.1 per 25 ft.

And in my X5, the headlights sit 36 inches above the ground, which would give me 428 feet of length in front for the lower horizontal, and much more than that for the higher horizontal--NO WAY!!

Al wrote, "And in my X5, the headlights sit 36 inches above the ground, which would give me 428 feet of length in front for the lower horizontal, and much more than that for the higher horizontal--NO WAY!!"

Yes, WAY! The US uses a fixed vertical aiming declination angle of 0.4º, which would give a lighting distance of 430 feet to the cutoff side reach with 36-inch headlight centers. With the legal maximum headlight center mounting height of 54 inches and the 0.4º fixed vertical aiming declination angle, the distance lighted on the lower cutoff side would be 645 feet! The European aiming specification is a 0.573º vertical aiming declination angle for headlamps up to a certain mounting height, but is increased for light centers that are higher than normal passenger cars. I believe that both aiming standards are wrong (in different ways) and headlights should be aimed for a lighted maximum distance of say 350 feet to the lower cutoff, regardless of what the mounted centerline heights of the headlights are.

ok guys, do we have an answer? It seems like everyone is having different opinions.

A moment like this I can't help asking how new cars with harmonized "Zs" are aimed. Maybe someone here have a really new car with untouched factory aimed "Z" cut-offs can do some measurements for us?

Tom,

if indeed the higher, right hand side of the z-pattern is actually up at an angle, and not down at a lower angle, then you have E-code lamps, not DOT. If so, you must aim them accordingly. I think the standard is 3.5 inches down at 25 feet. Hopefully Ekooke or someone else will correct me if I'm wrong.

show us pics of the beam pattern !

OK guys, after all the mumbo jumbo--and we all apparently know the rules--all I can say is that my X5 is now currently aimed higher than when it came from the factory, and that the lower horizontal on the Z on BOTH beams dips more than 2.1 inches per 25 feet. FACT.

Also, this aiming has the higher horizontal of the Z in a very slight downslope, it is almost running parallel to the level surface. If I aim only 2.1 inches per 25 feet down, I will have that higher horizontal running parallel or on an upslope. That's why I have it aimed lower. The Hella light fixture in my X5 is labeled DOT, but the projectors might be e code for commonality.
Rebember both "sources" of light (meaning lower and higher horizontal)are mounted at the same height, but one aims much higher than the other. The optical output for both is not the same.

Al,
Of course one part of the beam pattern will "aim" higher than the other; that's the whole idea! The LH portion of the beam is for lighting the road ahead of the driver WITHOUT offending/endangering oncoming drivers, while the RH portion of the beam is for lighting the curbside of the road to see deer, pedestrians, and roadside signs.

Hey Tom,
I personally aim mine as follows: I still use the standard US vertical setting of 2.1" drop @ 25ft. (as per left side of 'Z' cutoff line), and the driver's side lamp HORIZONTALLY I set parallel to car (so on a foggy night you can see that the beam is running exactly parallel to your yellow line in the lane, BUT, contrary to standard practice, I myself adjust the PASSENGER SIDE horizontal aim so that AT THE FARTHEST VIEWABLE POINT visible from driver's seat, that beam sits on top of the driver's beam. This DOES help to keep both lights looking like they put out even outputs (from oncoming traffic view), and if you have projectors, keeps the colors at prism stripe looking exactly the same shade of color (from a distance at oncoming view). And I believe it also keeps a slight amount more light right in your lane (does not take away hardly any light from ditch). Mainly just makes lights look more even from far away. This is how I prefer to do this though. The way to tell when they are correct is when you are really close to a wall (shining your lights on it), you will see that you have the 2 Z patterns on each side, but as you back up straight, you will see the driver's side stay in the same spot, and the pass side beam will slowly move closer to the driver's beam. And when you back up, if you EVER get to any spot where you can percept that the pass side beam is PAST the driver's side one, then it's adjusted too far to the left. You only want it so the pass side beam sits right over the top of the driver's beam at the farthest viewable distance. But like I said, I much prefer my lights this way. After a couple weeks of driving this way, your eyes will ADAPT to the beam apearing like it's moving on you as you see it's reflection on things while you drive, and it just looks and you precept that movement as being totally normal.
Like I said, this is not standard practice I don't think, and many people here may cringe at how I prefer to aim mine, but maybe you wanna try it for a few nights and see if you like it that way.

Ahh!! Josch, so this way you eliminate the ugly "dark spot" seen far away betweenn the two Z's, (optical illusion just because it is less illuminated than the surroundings). I think I might give this a try. Good idea.

I am 99.9 percent positive that my projectors are DOT units andthe cut-off and beam pattern look identical from this pic in the FAQ.

DOT-compliant headlights with the "harmonized" beam pattern will often look very similar to e-code lights. The only real difference is that US-DOT insists on a lower candela output at the "hotspots".

Yeah Al, NO more 'dark spot' I never knew life as having one, because I've had my lights adjusted this way since day ONE and I'm still glad

"DOT-compliant headlights with the "harmonized" beam pattern will often look very similar to e-code lights. The only real difference is that US-DOT insists on a lower candela output at the "hotspots"."

So how can you tell if a projector is DOT or ECE if they both have harmonized beams? Does it say on the projector (sticker or something?)

"So how can you tell if a projector is DOT or ECE if they both have harmonized beams? Does it say on the
projector (sticker or something?)"

It's cast into the outer lens covering of the original housing, but if you're working with OEM factory projector units that have been removed from the housings, a sticker or casting mark on the projector housing will (may) tell you.

Josch, do you have a picture of your cutoff on the wall, just so i can see what you mean? is the passenger's lower "Z" piggybacking the driver's upper "Z"????? THanks!

Jien,

if you look at the picture above, visualize what happens as you back out of the driveway. Now imagine the passenger side beam pattern getting closer to the driver side beam pattern. If you back up far enough, they will meet. I believe that's what Josch means.

Yeah, that's exactly what I mean. When I'm parked near a wall, my beam looks just like in the pic above. You can't see it collide and sit on top of the other beam until you are like mega far away. (you need a big parking lot to see it). I do mine in my back yard on the huge rear lawn. It's several hundred feet away before they sit on top of each other. Even as near as 3-5 car-lengths away from the wall, my beams still haven't even met yet. It is very gradual. Also, the final step to checking my aim, is to make sure that from the oncoming car view in the opposing lane, that both lights look the same intensity, and as I duck down, the intensity of both lights appears to brighten the exact same as the other one. It just looks less tacky too me, and I feel like it is more fine tuned and not so rough around the edges when I know that I'm right-on

thanks! i get what's going on now? oh btw Tom, how are you lights working out for you? Did you put em on your CRX yet?

What CRX? I have X5 HID projectors retrofitted in my 1998 Accord...

i was talking about geepherder hahaha his name is tom also

Jien,

no, I never realized how much work this was. I've had my wiring harness done for the longest time, as well as the projector swap. I've been copying my fenders amd header panel with fiberglass on my off days, and have one last fender to go. For now, I have no header panel on there, only some red junkyard Civic fenders on both sides- looks pretty hillarious.
Once I finish these, I'll need to fab some mounting brackets for the new lights, cut into my new panels, and mold it all together to make it look right. I want to get this all done before January since I'm going back in the military- no date set yet.

I'm not going to read any of the above discussion. This cannot possibly be this difficult!

Tonight, I used ekooke's suggestion and use the aiming directions from http://www.autooptiks.com/aiming.html. All I have to say is that I'm pretty pleased with the result. Except for that I almost got in trouble with the security at Home Depot for taping lines on the back wall to aim at 10PM. My car is lowered, so I actually did 2.5 inch drop in the 25ft distance. Enough light to see and not blinding oncoming traffic either, and I'm actually not experiencing the "dark spot" between the beams like what Josch and Al was saying. so I'm happy after all. Thanks boys.