HOW TO: aim HID headlights

[linuxglobal]

I came up with this diagram a while back. The others agreed it was accurate as a guide. The only value that may vary includes the width between the beams (pic says 3-4 feet) however that varies by each vehicle.

I think it should be fairly useful for members that want to use an aiming guide instead of asking around each time.

Drops from red line are the following.

DOT:2.1-2.5 inch
ECE: 3 inch

Good luck

[NOTSOFAST]

I think you should make it clearer that the 2.1"-2.5" is the distance between the upper part of the step and the centerline of headlight, bcs it looks like it's measured fron the bottom part of the step.

[linuxglobal]

k ill zoom it up a little and point to the top gap. Thanks notsofast.

[skygtr]

when retrofited already, is it possible to use the stock aiming pivot to aim? OR this had to be done prior to mounting the projectors on the headlights? wondering if I have to reaim my projectors since they are already retrofited by someone. I hope Im not blinding anyone on the road.

[linuxglobal]

you should be able to aim them using the stock adjustment screws. Its the retrofitter's responsibility to adjust them horizontally and to fix the rotation angle of them.

I know some gm vehicles tilt the entire lamp but in any case the stock aiming screws or an alternative method has to be setup for later adjustment.

[silva95teg]

Every diagram i have ever looked at uses the lower step at 2.1 inches down , not the higher one ...... which one is it? I used the lower one and i can see my cutoff on the ground on the road a fair ways up and i have never been flashed. That may be because i drive a lowered car though.

[linuxglobal]

it shouldnt really matter if the car height is lower/higher, at 25 feet you should aim the cutoff at 2.1 DOT under the red line and 3 for ece. DOT is the highest at 2.1 inches.

I guess if you feel that you need more light you could aim it higher, but these are the general aiming guidelens, They are meant to help you aim your lights in all perspectives, vertical adjustment should be allowed to be adjustable later on just in case you do lower or raise the car you need to have control over that.

btw any pics of ur cutoff. Most hids will have a cutoff on the ground, even good halogen reflectors have them. Its okay if you can see the cutoff on the road, just as long as its not too close to the car.


Good luck

[silva95teg]

i have a couple but they have to be resized , i aimed it by driving up to the right up to the wall , marking the lower step and then about 2.5 inches below it , i then backed up and aligned the lower step with the mark 2.5 inches below where it was at 0 ft i guess it woul dbe the same as using the higher step.

[rly44]

If you look at the Automotive Lighting FAQ stickied in this forum, you'll see that they say to aim using the lower step. This is their reasoning.

"The lowest cuttoff line should always be used for aiming. This would be the left part of cutoff line (unless u are in UK). The right side of it cannot be used as a reference, hight will vary depending on manufacturer and model. "




Any mods have an opinion on this? Which way is correct and if the higher step is suppose to be used, then the FAQ needs updating.

[silva95teg]

that is the diagram i was referring to ... i couldnt remember where i saw it. It isnt the only one i have seen using the lower step though, while trying to find that one back i saw two others in a google search both using the lower step. Like the flare ece cutoffs would have to use the lower.

[linuxglobal]

i still think its the top cutoff. That just limits glare even better. I guess it also depends on your projector. These are for the generic e46 or e55 step cutoff. Im sure the tsx could be aimed differently.

Let me know guys and ill alter the diagram. I originally thought it was the lower step too but i changed it later in this post. IF we have the correct answer brought out that would be the best.

Thanks,

[NOTSOFAST]

NO, NO,NO . It's the lower step that has to be used when measuring drop from the centerline. The top step goes higher the farther you go so you would end up aiming your headlights to the ground with that method. The botton step is the one that should drop 2.1-2.5" at 25Ft. You cannot drop the top step at the gradient of 2.1-2.5" for 25Ft or you would not be able to see anything above cutoff such as street signs etc. Fix the diagram please Linux before there's 10 new threds asking on how to aim headlights. :drinkers:

[linuxglobal]

I think you should make it clearer that the 2.1"-2.5" is the distance between the upper part of the step and the centerline of headlight, bcs it looks like it's measured fron the bottom part of the step.

O man changed it around for no reason... LOL new pic up/old pic

[NOTSOFAST]

I just saw my post ....Shiat, my bad was thinking something else and wrote down the wrong thing...LOL sorry about that ! I guess that's what happens when you have a lot on your mind I can't even remember why I wrote that...maybe bcs that centerline is supposed to be in between the lower and higher step...

[linuxglobal]

u mean the purple line that i have should be somewhere midslope,?? not completely at the beginning of the step?

Let me know . i want to get this right for future use.

Thanks