GrantG

I used to have a 996 with the Bi-Xenon headlights (Xenon for hi and lo beams) and they made high speed night driving alot more confidence inspiring here in the mountains of Colorado - you could really see clearly a good distance down the road.

Is it true that the Lightronics retrofit kit for the 993 is only Xenon for the low beams? Is there an alternative to get a really bright (preferably Xenon) lights for the hi-beams?

914und993

I have settled on a good solution, but it wasn't exactly simple. Elements are:

1. CATZ HID (xenon) low beams
2. Philips 100w H1 bulbs in the high beams
3. 14 ga wiring more directly from battery to high beams via relay

The hard part was #3, a simple relay circuit switching the high beams wouldn't allow the fog lamps to work properly. The relay circuit provides higher voltage/current to the 100w bulbs giving a whiter, brighter light. There is a significant voltage drop on the stock wiring when you just install 100w bulbs in place of the original 55 watt bulbs, but its better than nothing. There is some concern that too much current passes through the stalk switch without a relay circuit, but several on this board report no problems.

I haven't heard of anyone with an HID Hi and Low beam solution for the 993 headlamps.

Chip

graham_mitchell

Actually, this could be worse than leaving it alone. You may achieve LESS light output, plus more electrical power consumed and more heat generated both in the wiring and the light assembly.

There is a thread somewhere written by a rennlister who put this very question to the test by measuring light output with a light meter. The voltage drop was enough to heavily reduce the output of the 100W bulb, to less than the 55W one.

Incandescent light bulbs are very sensitive to drops in voltage.

Upgrading to 100W high beams is only recommended in conjunction with the correct use of relay and heavy duty wiring.

914und993

Graham, that was me that made those light output measurements. I keep thinking there might have been something wrong with my methodology, since some ( Dan 96C2 St.Louis ) believe it does help.

I'll agree its good to be leery about just swapping in the 100w bulbs. Dan has had no problems, but there have been reports in other 911s (not in the 993 that I know of) of the stalk switch failing because of the heat from the higher current.

Chip

graham_mitchell

I have read the same results in other places, so it sounds about right.

As for the original question, the problem with HID bulbs is that they can not be used for flashing, which makes them unsuitable for high beams. The only way around this that I am aware of is to mount an HID bulb behind a shield and keep the bulb permanently on. The shield is then moved quickly to allow the light through when required. I have heard of aftermarket kits for this, but I am not sure of the sizes they are available in, or whether they would fit in our headlight assemblies.

I have no doubt that if you managed to install HID high beams, the results would be fantastic for night driving!

Mark in Baltimore

I know the HID's don't achieve maximum light output as soon as you hit the switch, but wouldn't that characteristic HID ignitor start up "flash" draw enough attention?

GrantG

I think the Bi-Xenons in my 996 had an auxillary Halogen bulb for flashing - it was a nice system. Thanks for all the replies!

Toga

I have 100W bulbs for the hibeam, and didn't have any problem with them. But they still look weak compare to the Xenon low beam. I know it's possible to have bulbs of more than 100W but there I would be concerned about the alternator and the wires.

JP

STLPCA

Chip
Actually it's me, not Mike. We are frequently confused with one another because we're both good looking and drive slowly around race tracks.

I've run 100W highs for a few years w/o any discernible problems. However, in my urban driving the highs are rarely on for more than a few minutes at a time. There is a noticeable improvement over the oem 55W, but as Toga said, they pale in comparison to my HID lows.

Grant
It is possible to convert the highs to HID using an H1 conversion kit (e.g., Catz, Autolamps, etc.), but ballast/igniter placement would be a problem due to limited space, the flash ability mentioned by Graham would be an issue, and the poor design of the headlight reflector/lens would be exacerbated.

lexpilot

Which HID Lows, specifically, please. I know there's been discussion about these headlamps not being easily upgraded but have you found a solution. I was spoiled by the nifty zenon lights in my 99 Lexus 400. Factory option, work great.
TIA, Robin

Mark in Baltimore

If I'm not mistaken, the factory HID's (Litronics) are still a legal, albeit expensive upgrade, for cars not so equipped.

Catz made an aftermarket HID kit that many of us bought from Lite Swap. The installation is not difficult at all. Additionally, there is another supplier (in England?) whoe can supply a kit. try doing a search since this came up fairly recently.

graham_mitchell

Mark,

it is http://www.autolamps-online.com/ but they now have a dedicated HID website at:

http://www.hid-online.com/

pjc

I thought a lot of the US guys were removing the aftermarket Catz for legal reasons? I have C.A.T. set on my 993 (low beam) and they are great - and so far pass the UK M.O.T. test.

The bi-zenon system with the moving disc is an aftermarket HID kit for the 964 I believe.

PJC

STLPCA

I have the Catz H1 conversion with which I remain quite pleased. As far as I can tell, performance equals the factory Litronics & my Catz install is just as clean w/the added advantage of being able to convert back to H1 halogens in about 15 min w/no tools if e.g., an HID bulb dies. An archive search will reveal that, unfortunately, these kits are no longer easily purchased in the US.

I haven't heard of anyone who has removed a conversion.