HID conversion DIY finished..Woow
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From: Down the rabbit hole
Originally Posted by Georges Rebeiz
By the way Graham , I don't think that Factory OEM 993 HID come for the high beam but only for the low.
Originally Posted by mborkow
graham, the link you sent states on it that the kit is only for off road use.
Rennlist Member
Joined: Apr 2003
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From: Seattle, WA
The problem with using HIDs for high beams is the warm up period for these bulbs. They don't produce full light right away and this is a problem when you're on the highway (at speed) and require illumination immediately.
The cars that use HID for high beams have an active reflector that basically re-aims the low beam (which is already warmed up) higher to supplement the high beam bulbs.
Thanks,
Peter
The cars that use HID for high beams have an active reflector that basically re-aims the low beam (which is already warmed up) higher to supplement the high beam bulbs.
Thanks,
Peter
Three Wheelin'
Joined: Mar 2002
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From: Belgium
[QUOTE=graham_mitchell]That sounds right, but the low beams are so improved that you will rarely need the high beams any more.
You're right Graham, I have the xenon option on my car and they are only for low beam. They're so good that I never used the high beam which looks "pale" and yellow compare to the xenon.
There is also a option of switching the 55W high beams for 100W. But here in Belgium that's illegal (
)
You're right Graham, I have the xenon option on my car and they are only for low beam. They're so good that I never used the high beam which looks "pale" and yellow compare to the xenon.
There is also a option of switching the 55W high beams for 100W. But here in Belgium that's illegal (
)
Thread Starter
Instructor
Joined: May 2003
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From: Beirut,Lebanon
Originally Posted by Toga
There is also a option of switching the 55W high beams for 100W. But here in Belgium that's illegal ( )
)In the event of switching to 100Watts lamps don't you have to add a "relais" in order not to overheat the wires and the switches??
Three Wheelin'
Joined: Mar 2002
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From: Belgium
Hi Georges,
honestly I don't know! I did that on all my every day cars without ever having any problem. On BMW, there is already a relay which protects the circuit. On Porsche I don't know, but I would bet they do have a relay too.
honestly I don't know! I did that on all my every day cars without ever having any problem. On BMW, there is already a relay which protects the circuit. On Porsche I don't know, but I would bet they do have a relay too.
Burning Brakes
Joined: Jun 2002
Posts: 933
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From: Larnaca
Gents,
adding 100w bulbs without relays (to take the extra load from the bulb's increased wattage) will overheat cable/wiring and more than likely lead to fire - I have read about a couple of people -not sure if it was on Rennlist- whose cars caught fire this way.
Either avoid the 100w bulbs, or take to a pro and install relays.
Best regards
Emilios
adding 100w bulbs without relays (to take the extra load from the bulb's increased wattage) will overheat cable/wiring and more than likely lead to fire - I have read about a couple of people -not sure if it was on Rennlist- whose cars caught fire this way.
Either avoid the 100w bulbs, or take to a pro and install relays.
Best regards
Emilios
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From: Down the rabbit hole
Originally Posted by Georges Rebeiz
Toga
In the event of switching to 100Watts lamps don't you have to add a "relais" in order not to overheat the wires and the switches??
In the event of switching to 100Watts lamps don't you have to add a "relais" in order not to overheat the wires and the switches??
A 55W 12V bulb should have a resistance of about 2.6 ohm
A 100W 12V bulb should have a resistance of about 1 .4 ohm
Let's assume the resistance of the wiring and switches is 0.1 ohm, and the power source has a potential of exactly 12V.
The voltage across the 55W bulb in this case would be 11.6V (97% of nominal voltage), and 0.4V across the cable.
The voltage across the 100W bulb would be 11.2V (93% of nominal voltage), with 0.8V across the cable.
The power dissipated in the first cable would be 1.6W, and 52W in the bulb.
The power dissipated in the second cable would be 6.4W, and 90W in the bulb.
You can see that the power dissipation of the cabling increases by a factor of 4.
The effect on the light output is more severe than it seems by looking at the figures because the relationship between light output and voltage is not linear.
The 55W bulb at 97% of nominal voltage will produce about 92% nominal light output.
The 100W bulb at 93% of nominal voltage will around 78% of nominal light output.
The net result? Only 46% more light but nearly double the electrical power consumption.
If the resistance of the circuit were even higher, enough to drop the voltage across the 100W bulb to 82% of nominal voltage, then the light output would be the same as a 55W bulb!
Last edited by graham_mitchell; Oct 29, 2004 at 08:21 AM.
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From: Down the rabbit hole
I should add that I am finding it hard to get hold of reliable data WRT holgen v HID light output, but if the lumens per watt efficiency of HID is ~7 times that of halogen, as this site suggests, then the typical 35W car HID light will produce around 4.5x the light of a 55W halogen, and whiter light.
A few other sites give a ratio closer to 3x.
A few other sites give a ratio closer to 3x.
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Burning Brakes
Joined: Nov 2002
Posts: 801
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From: United Kingdom
Graham,
Don't know the precise details but I believe the Litronics kit is expensive because it comes with replacement bowls which have special internal finish zones that overcomes the need for "self-leveliing" equipment.
I have an after-market HID kit on my 993 and NEVER get flashed - have factory fitted zenon on my Ford Focus and always seem to be getting the bird from on-coming drivers!
PJC
Don't know the precise details but I believe the Litronics kit is expensive because it comes with replacement bowls which have special internal finish zones that overcomes the need for "self-leveliing" equipment.
I have an after-market HID kit on my 993 and NEVER get flashed - have factory fitted zenon on my Ford Focus and always seem to be getting the bird from on-coming drivers!
PJC
Three Wheelin'
Joined: Mar 2002
Posts: 1,548
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From: Belgium
Thank you Graham,
you sound like the man of the situation!
could you tell how much bigger should be the cable section for 100W bulbs? Or what should be the ideal section for those 100W bulbs?
If the section is bigger, the heat dissipation is lower. May we say that the power of the 100W would be restored to a higher % of the nominal value?
you sound like the man of the situation!
could you tell how much bigger should be the cable section for 100W bulbs? Or what should be the ideal section for those 100W bulbs?
If the section is bigger, the heat dissipation is lower. May we say that the power of the 100W would be restored to a higher % of the nominal value?
Addict
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From: Herefordshire
Apart from all the above, you need to remember that the high beam bulb socket is plastic - high wattage bulbs will deform the mount, misaligning the bulb in relation to the reflector, if not starting a fire ....
HTH, cheers, Maurice
HTH, cheers, Maurice
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From: Down the rabbit hole
Originally Posted by Toga
could you tell how much bigger should be the cable section for 100W bulbs? Or what should be the ideal section for those 100W bulbs?
If the section is bigger, the heat dissipation is lower. May we say that the power of the 100W would be restored to a higher % of the nominal value?
If the section is bigger, the heat dissipation is lower. May we say that the power of the 100W would be restored to a higher % of the nominal value?
- heavier duty cables
- shorter cable lengths
The best result is achieved by using short runs of 10 or 12 AWG cable directly from the battery to the bulbs, using relays switched by the existing wiring. Don't forget to use appropriate fuses close as close to the battery as possible, and two create two fully independent systems (for added safety) i.e. a fuse for each headlight.
Nordschleife Master
Joined: Aug 2004
Posts: 5,622
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From: Austin, Texas
you know, here is sort of my problem with the HID kits....
I like the look of the headlights and fog lights on at the same time.... I agree that the HID lights look tons better, but then they make the fog lights look **** yellow....I feel like the combo looks not so good, but I like the fog lights.... Any opportunity to upgrade both to similar kelvin strengths/similar color so they match?
I like the look of the headlights and fog lights on at the same time.... I agree that the HID lights look tons better, but then they make the fog lights look **** yellow....I feel like the combo looks not so good, but I like the fog lights.... Any opportunity to upgrade both to similar kelvin strengths/similar color so they match?
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From: Chicago NW suburbs
Originally Posted by mrsullivan
you know, here is sort of my problem with the HID kits....
I like the look of the headlights and fog lights on at the same time.... I agree that the HID lights look tons better, but then they make the fog lights look **** yellow....I feel like the combo looks not so good, but I like the fog lights.... Any opportunity to upgrade both to similar kelvin strengths/similar color so they match?
I like the look of the headlights and fog lights on at the same time.... I agree that the HID lights look tons better, but then they make the fog lights look **** yellow....I feel like the combo looks not so good, but I like the fog lights.... Any opportunity to upgrade both to similar kelvin strengths/similar color so they match?