DKC64

In the standard Bi-Xenon headlight, I have not been able to find a figure showing what bulb is for what.

I can see the main lens which is clearly the Xenon. This is switched on for low beam, and remains on for high beam.

Below the Xenon there is a H7 bulb which comes on for high beam only. The light pattern from the Xenon did not seem to move between low and high beam.

So is the high beam light produced by the H7 or by the Xenon. If it's by the H7 then what's "Bi" about the Bi-Xenon?

Thanks for any wisdom in this aspect!

DKC64

Been doing some Google searching...

Why I'm confused is that according to this page, we have Xenon D3S low beam, and H7 High Beam. If that is the case then how do we have "Bi"-Xenon?

http://www.lightbulbs4cars.com/porsche%20bulb%20guide

And if we already have Bi-Xenon, why are there companies selling a 991 H7 to HID conversion kit? So we end up with Tri-Xenon?

http://www.carxenonhidkits.com/911-9...e-911-991-2012

Thanks!

liljohnny

There is a shield that partially blocks some of the low beam xenon bulb light to give you a nice clean, controlled cut off line as not to blind oncoming drivers. When you activate the high beam, the shield drops on the low beam bulb exposing the entire low beam light. this scatters light from the low beam bulb over a larger area....in addition, the H7 bulb fires up supplementing the full xenonbulb output with even more light. the "Bi" in Bixenon, refers to the moving shield in the low beam bulb projector making it a low beam, as well as a high beam. For many manufacturers, this is adequate, Porsche decided to add even more light with the additional H7 bulb.....awesome imo!

WCE

The H7 halogens are also your "flash to pass" lights.