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Beam Pattern Issue W/ HID From Groupbuy


SM 2003
Full Member
Dec 5, 2002
Hello fellow AVers!

I bought an HID kit from the group buy, and have a question for those of you who also bought them about your beam pattern. ?I have an '03, and although the light is bright & bluish/white, the pattern is messed up and not "clean" (there are bright areas and slightly darker areas) when projected ahead of me. ?Is this what the rest of you have experienced? ?My Acura's HID lights (they were OEM) did not have this at all, so I figure it is because of the stock halogen reflector set-up is not geared to the HID specs. ?

Also, do I need to raise the height of my lights (they seem to be projecting fairly close to the vehicle, and NOT projecting way ahead of me.)

So what I want to know is, is this 'messy' beam pattern what you all have too, or is there something wrong with mine? ?Thanks!

Hi Wiz,

I've got the HIDs on high and low. The high beam is pretty crisp with sharp cutoff. The low beam is less than perfect. I've checked out the pattern based on where it lands on cars parked along the roadside and it appears to cut off sharp enough so that it isn't shining above the drivers door mirror.

I never noticed how crist the stock lights were. One thing is for certain, I haven't gotten flashed by oncoming drivers!

If you raise the aim you'll probably atract unwanted attention.


Thanks for the input on raising them up. My main concern though is the pattern. There is a clean cut-off line at the top, but the overall wash of light is not consistant and solid. you can see distinct areas that are not getting an equal amount of light. Does your lowbeam light area look this way as well?

It does vary in intensity. I can't say if I'd call it good or bad. When I first put in the low beam I was so impressed with the light output I ordered the high beam the next day.

The low beam has the cup reflector in front of the bulb so all the forward light is reflected from the back. The way the reflector is all faceted it looks like it would give a wild beam pattern, I have a horizontal hour glass shape !><! in the center and then a radial pattern of lighter and darker areas from the center. Nothing I would call problematic.

Maybe changing the o-ring thicker or thinner would move the bulb's hotspot in or out of the reflector cup and change the pattern.

It would be interesting to all if it made big changes.