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I've got a very apparent line of delineation where my headlights drop off in front of me. Very noticeable when going down even a slight incline. High beams meanwhile, light up the universe.

Anybody else noticed this?:confused
 

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1. Find an area with a flat, level surface that abuts a wall.
2. Pull the car up to the wall, almost touching and turn on the low beams.
3. Mark the upper cutoff line of the headlight beam pattern with some masking tape.
4. Put some more masking tape 3 inches below and parallel to the first line
5. Back the car up 25 feet.
6. Adjust the headlights until the beam cutoff aligns with the lower tape line

After doing this, I have adequate distance on the low beams and have never had anyone flash their brights at me.

Turning the adjusting screws an arbitrary number of turns is not very useful, as it assumes a particular position of the lights in the first place.
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noz34me said:
I've got a very apparent line of delineation where my headlights drop off in front of me. Very noticeable when going down even a slight incline. High beams meanwhile, light up the universe.

Anybody else noticed this?:confused
I know what you're talking about. Get used to it. There is no adjustment.

All projector style headlamps have this very sharp "cutoff" of the beam.

I have two other cars with HID lights in a projector housing that do the same thing. The GTO is my third vehicle with this "feature" and it has the same effect as the HID's even though the GTO is just using halogen bulbs in the projector housings. My wife hates it. Gets her seasick watching the cutoff line bounce up and down in front of her so she uses the high beams at every opportunity on all three cars. Doesn't bother me as much.

It's most annoying on narrow roads especially if you have trees or other structure lining the sides of the road. It's not as noticeable on divided highway where you don't have structure close by.

Not sure this is an improvement in lighting technology.
 

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Wing_Nut said:
I know what you're talking about. Get used to it. There is no adjustment.
.

Not true - one screw on each side will change the setting. Very easy to adjust. Drivers side is hard to find, must look down through the slots in the radiator cover - might even need a flashlight, passenger side a little easier to find, about 4-5 inches down from top and behind radiator cover. Go tweak them like in the post above and you will be much happier. Brights are another story.
 

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blackonblack said:
Not true - one screw on each side will change the setting. Very easy to adjust. Drivers side is hard to find, must look down through the slots in the radiator cover - might even need a flashlight, passenger side a little easier to find, about 4-5 inches down from top and behind radiator cover. Go tweak them like in the post above and you will be much happier. Brights are another story.
There is no adjustment for what he's talking about. Yes, like any headlight module, there are provisions for adjusting the aim of the beam.

But, this isn't an aiming problem.

A typical halogen bulb in a typical large concave reflector produces a very gradual and barely noticeable transition from lit area to darkness. It's a focusing issue. The large reflector produces a softer focus and therefore a smoother transition from light to dark.

The projector housing uses a much smaller convex lens (not a reflector) to focus the beam more tightly. The result is more light in critical areas but a very sharp transition from lit to unlit areas in front of the car. This is usually noticed in the vertical light dispersion pattern as a horizontal "line" that bounces up and down in front of your car. The horizontal dispersion pattern doesn't seem to get noticed as much.

You can change the headlight aim but that only changes the height of the "line" bouncing up and down in front of you. It will have no effect on the focus or dispersion pattern.

Take your GTO out on a dark narrow road. Look for the area at the limit of your low-beams. Now drive the same road in a car with typical halogens/reflectors. See the difference? That's what drives some people nuts.

Suggest before anyone pops $800+ for those cool blue-white headlights on any new car, that you drive the car at night on a dark road and see if this bothers you. After owning two HID equipped cars, I wouldn't spend a nickel for this on a new car. HID's are not really better or worse than well designed halogens but they can be annoying to some people.
 

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Just get HID lights. The cut-off is still there but the light travels and reflects 100x better so the problem is not as bad.

http://www.xenonpros.com/mc5000k.html

That's where I got mine. Plug and play. Took me about 20 minutes to install.
I totally agree...HID's work very well on these cars and are much better than the yellowish halogens that come stock. And the way it travels and reflects off signs is very helpful. Try these:

http://cgi.ebay.com/ebaymotors/H11-...QQcategoryZ36476QQitemZ130071568058QQtcZphoto
 

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I did the HID conversion on my low beams (make sure to remove the DRL Relay in the under hood fuse box). The output is actually 3x brighter then halogens. The sharp cut off of light as other members stated is due to the type of headlamp units that the GTO's have (Projector).

If you want more light on the road in front of you with a more broader light pattern similar to traditional (Reflector) headlamps, then install a HID conversion kit in the fog lights. they take 9005 bulb bases perfectly. They also have a adjustment knob on the back of the housing that you can turn with your fingers to bring the light pattern up or down.

I have a kit in the fogs also.
 
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