UncleRobb

With the HID low beam being as great as it is, the incandescent (halogen) lamp driven high beem gets a little old: The light appears not to be too bright, somewhat yellowish and when powed up, the lights are somewhat sluggish and need a few tenths of a second to reach full intensity.

A solution might be to use a modern high intensity LED: i) the color of the light is rather white than yellow and thus better matches that of the HID low beam; and ii) there is full intensity as soon as being powered up. Unfortunately, there seem to be very few (if any) suitable H9 lamps on the market.

Perhaps somebody has tried the Osram 27 Watt



or the Cree 24 Watt (4x6 W) LEDs,



both available from http://autolumination.com/headlights.htm for $34.99 each. If one assumes that the LEDs are 2.4 times as efficient as the halogen lamps, then both LEDs are approximately as bright as a 65 W H9 lamp.

What do you think?

Thanks, Robert

y2krtaf

Interesting,would like to know more myself.

raysk

I was thinking about the same thing. Wish someone would test it and let us know. maybe one of the forum vendors that sell LED's for other applications?

JW Motorsports

Drop in led bulbs aren't quite there yet. Those will produce a better looking light. They will not be good enough for high beams.

RnLi

Agree with above......

Nice looking and very bright WHITE light BUT they do not project down the road. As such, probably for "claiming" rights or show only.

Oh, tried a set in another car. Worked only as stated above. Notice in the ads...they speak of brightness, but have no mention of visibility DOWN the road.

y2krtaf

Why does an led come up short?
I'm sure theres some cool science to it.

Mad*Max

MRhine1

I tried the Cree bulbs about a year ago. They much worse than the stock high beams. My low beams with my upgraded matching fog light bulbs were much better when going down road. Just ended up going back to the stock highs.

UncleRobb

Thanks for your quick answers, guys! Special thanks to JW@JWMotoring.com, RnLi, and MRhine1 for very helpful explainations.

Let me try to come up with an answer from what I have just learned in this thread. The high beam projector lights in our C6es are probably built like this:



Source: http://en.wikipedia.org/wiki/File:He..._schematic.png

The light emitted by the filiament of the H9 lamp is reflected and passes a plano-convex lens to give rise to an almost parallel beam. The shield shown in the picture is of course not present in the C6's high beam lights but rather (in a fixed version) in its HID low beam projector lights. Of course it would be nice to have a combined HID system for low and high beam as shown in the picture and I suspect that the new C7 has it.

Back to the high beam light in our C6. The optics are constructed for the light emitting filiament of a H9 bulb, a spiral coil of say 1 mm in diameter and 5 mm in length. When a LED lamp of the types I have shown in my previous post is inserted into the projector system, the individual LEDs (4 for the Cree and probably 9 for the Osram lamps) are a few mm's away from where the H9 filiament would be located, which probably leads to a beam that is much broader (and also somewhat irregular), perhaps similar to the one created by the fog lights. So from a distance the high beam light created by the mentioned LED lamps should be considerably less intense than that from the original H9 lamp.

raysk

Thanks, JW. i thought that LED's might not yet be quite ready for high beams. I trust your advice. So far I've purchased your super bright reverse LED's and rear compartment LEDs, and both were significant improvements over stock, just as you stated. that's not the case with some other LED applications I've tried ordering from others. You do not offer LED products until you know they are good for us. Thanks for your honesty, and the testing you do before offering such products.



Good explanation from robb too. in summary, it sounds like you are saying that geometry of the C6 headlight assemply is designed to project light best down the road from a "point" source of light, which an LED is not. To get the high watts, they need to use multiple LEDs spread that are spread out.

I've noticed at some LED light sites a pretty high watt LED replacement for the fog lights, and I am thinking about trying them. It appears like the LED is designed much like the super bright reverse lights offered by JW. I don't want to go to HIDs for the fogs, i like simple applications. what do you guys think of that?? Thanks.

UncleRobb

raysk, in order for an alternative light source to work with the projector high beams found in the C6, it needs to be sufficiently small and at the very same place as the filiament of an incandeslescent H9 lamp. The first condition probably can be fulfilled by a single LED chip, but the second not.

Replacing the H10 42 Watt halogen lamp in the fog lights by some LED equivalent seems to be more promissing. Since the intensity of the lamp is much smaller, the reflector is bigger and the beam, in contrast to the high beam headlights, is very wide anyway. However, I have not tested this and the results might also be disappointing. E.g. I would not be surprised if the beam would turn out to be somewhat irregular.

ProjectWJ

They physically don't fit - figured I'd give it a go.
The diameter of the "light & electronics" sections won't fit through the inner portion of the projector. If you remove the stock H9 and look up in there, there's a second "ring" part of the projector that the light needs to fit through and the LED's are too wide... Just an FYI.