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Old 1st July 2006, 10:38   #16
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Yeah you can fit fog lamps in your zen without fiting a crash guard ...but you might have to drill holes somewhere in your bumper..


another option is like u said ...fittinga fog light/indicator combo in place of the side indicators on teh fron bumper ...you get Neolite ones for around 400 rs for a pair ....this was teh price in 2001 ...dunno whats the present price .

No idea abt Hella fog lamp prices ...be careful abt duplicate ones
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Old 1st July 2006, 10:59   #17
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Kaizer Sozay,

go ahead and fit any brand fog light, but do make sure it spreads wide instead of throwing long beam.
and the colour is yellow.

and FYI, use of heavy wiring and relays is most important.
you can use BOSCH relays.
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Old 9th July 2006, 02:16   #18
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Quote:
Originally Posted by speedsatya
Yeah you can fit fog lamps in your zen without fiting a crash guard ...but you might have to drill holes somewhere in your bumper..
another option is like u said ...fittinga fog light/indicator combo in place of the side indicators on teh fron bumper ...you get Neolite ones for around 400 rs for a pair ....this was teh price in 2001 ...dunno whats the present price .
No idea abt Hella fog lamp prices ...be careful abt duplicate ones
Ok I am only getting the Rectangular HELLA Fog lamps for 1700/- But i will have to cut my bumper.
Guys any suggestion where would be the best place to cut the bumper in the Zen to fit these fog lamps.
The acessory guy said that i should place them below the number plate.
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Old 9th July 2006, 10:04   #19
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i have seen some cars with two clamps coming out of airdams' corners below the front number-plate and 1 auxiliary lights fitted on each of them.

but i doesnot have any idea from where those two clamps are coming and to which they were connected to at their rear ends.
but it looks neat and no wire or clamp itself is visible easily from front.

but it certainly is a better idea than making big cuts in bumpers for wholelights. coz if you opts for big holes, you cant go for other shaped lights when u got bored of those older ones!
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Old 9th July 2006, 10:18   #20
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There are two basic types of auxiliary lights: fog lights and driving lights.

Fog Lights
Switching on the high beams does not improve vision in heavy rain or fog, it makes it worse. It illuminates the fine water particles, making the fog shine back in your face.

For dense fog and heavy rain the beam angle must shoot sharply downward toward the ground.

Real fog, if you've seen it at Mahabaleshwar or Khandala sticks to the ground 1.5 feet above the surface.

Therefore fog lights must be mounted low in the front bumper apron or bolt above it.

The fog lamps must spill a 90-degrees wide fan-shaped beam of light down onto the road, lower than and into the fog sticking to the road. Only then can you see better and drive safer. The beam fanout must not extend above the bumper.

Aligning the fogs
By SAE standards, the fog lights should be mounted 1 foot plus or minus 2 inches above the ground.
When viewed from 8 metres away, the top of the beams should drop 0.75 degrees.
Now sin(0.75 degrees) is 0.01309. Multiplying that by 8 metres, you get 105 mm (10.5 cm).
Find a white wall on a flat ground.
Drive up to the wall until your car nearly touches the wall.
Mark points on the wall, where the centres of your fog lamps are.
Now reverse the car 8 metres away from the vertical white wall.
Switch on your fog lamps. Align the beams so that the tops of the beams are 10.5 cm below the dots you marked.
Your fogs are now aligned to SAE spec.

Driving Lights/Spot Lights
Unlike foglights which must spill their beam 90-degrees wide, driving spotlights shoot a 15-degrees wide beacon for fast driving.

They augment the brightness and distance-range of your high beams, illuminating your path with bright light.

That makes it most effective for night-time highway cruising at speeds above 80 km/hr.

As driving spotlights are so bright and focused, they can
blind oncoming drivers as well as the car you're following behind.
Correctly aiming them is therefore very crucial.

Aligning the spots
By SAE standards, the fog lights should be mounted 2 feet plus or minus 6 inches above the ground.
The beams should shoot out parallel to the road (never above it). 8 metres away from the vertical white wall, spot lamps should throw a hotspot 2.5 cm below the dots marked.
------------------------------------------------------------

The fallacy about yellow lights
In the old days fog lights were yellow. In the old days French law required all cars in France to have yellow headlamps.
Remember the 1953 Fiat 1100/103 TV (Turismo Veloce) colloquially known in Bombay as डुक्कर (Dukkar) Fiat, came with a yellow foglight in the center of the grille.



Rayleigh's scattering law does NOT apply to fog droplets! Why? Fog droplets are still huge compared with the wavelengths of visible light. Thus scattering of such light by fog is essentially wavelength(color) independent.


In order to get yellow light you need a yellow filter. If you place a filter over a white bulb, you get less transmitted light, and less penetration. Designers of headlights have known for a long time now, that there is no magic color that gives great penetration.

An article from the Journal of Scientific Instruments, says, "It seems to be becoming recognized that there is no filter, which, when placed in front of a lamp, will improve the penetration power of that lamp".

A Russian scientific article, stated, "Investigations and practices of automobile traffic do not confirm any substantial advantages of yellow light over white light. The advantages ascribed to it may take place only in very thin fog or may be subjectively received by some drivers owing to their individual peculiarities of vision. Therefore, it does not make any sense to switch over headlights to yellow light, although the use of yellow light in special fog lights does not raise any objections." End of quote. The phrasing is quaint, but the meaning is clear.

So, unless you just happen to like yellow, save your money and forget about so-called "fog-lights." They don't exist.

Last edited by Ram : 9th July 2006 at 10:19.
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Old 9th July 2006, 10:24   #21
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ram, i guess you forgot to post the source link from where you copied this brilliant stuff and pasted here!
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Old 9th July 2006, 10:29   #22
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Quote:
Originally Posted by revharder
ram, i guess you forgot to post the source link from where you copied this brilliant stuff and pasted here!
Dear revharder:
Ouch, that stung! I'm sorry but I couldn't reacting -- a human failing.
None of my posts is copied and pasted.
It is the result of my research, of my personal experience (I got my Indian driving license in 1975, US license in 1985, Netherlands license in 1986, Australian in 1992, and Singaporean in 1997), also the result of reading many books over the decades and websites. The English articulation, calculations and scientific/engineering advice is entirely my own!
Ram

Last edited by Ram : 9th July 2006 at 10:41.
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Old 9th July 2006, 13:29   #23
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nothing beats experience ram

my two bits - a lot of members have already mentioned these aspects -

a problem in fog ( and other forms of precipitation that restrict visiblity) - back scatter - thats the term for the light scattered back (simple english eh!) towards the drivers eyes.

so its pretty obvious, low placed "fog lights" contribute to less back scatter ( and those placed on top of the roof simply blind the driver) in addition to (1) illuminating the road better owing to the proximity of beam to the road surface (2) utilising the property of common fog of having a reduced thickness close to the ground.

another point - hazard lights - using them in fog - although they do assist others in seeing you (and hence not ploughing into you) - the intermittently bright (modern cars have very very bright lamps, indicators, brake lights et al - tailing them in traffic can be painful on the eyes sometimes!) lights play havoc into the drivers night vision (and fog-vision)- again, owing to 'back scatter'.

don't most cars in european markets (not sure about US etc) come with small , low placed rear facing fog lights (usually red / white - aimed at the road, like some models of the Zen VX?) - i know they assist in reversing etc - what about visibility to traffic approaching from the rear ?
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Old 9th July 2006, 14:05   #24
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Quote:
Originally Posted by Captain Pings
nothing beats experience ram

don't most cars in european markets (not sure about US etc) come with small , low placed rear facing fog lights (usually red / white - aimed at the road, like some models of the Zen VX?) - i know they assist in reversing etc - what about visibility to traffic approaching from the rear ?
The rear-facing fog lights are usually extra bright red lights (brighter than the stop lights). Remember the Cielos and Nexias used to have two of them.
Cheap cars like the old Ikon had just one and expensive cars had two (bilateral symmetry).

Once while skirting the Kralingse Plas lake along the Boszoom road in Rotterdam, the Netherlands, I ran into a cloud of fog that had wafted out of the lake and turned on my red rear fog lamps. After coming out of the fog, I forgot to switch them off and got pulled over by a police car. He let me go out of consideration for my being a stupid foreigner with a California driving license.

The white lights IMHO were always reversing lights activated by a switch on the gear lever selector fork. They had to be bright too as they had to illuminate the path, one wished to reverse onto.
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Old 9th July 2006, 14:18   #25
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Speedsatya
you have installed Hella Micro DE fog lamps whats the reprot on them?
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Old 9th July 2006, 18:11   #26
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did anyone try using LEDs to make fog lamps. i am thinking of buying a few and trying it out this weekend.
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Old 10th July 2006, 08:51   #27
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Quote:
Originally Posted by ram
Dear revharder:
Ouch, that stung! I'm sorry but I couldn't reacting -- a human failing.
None of my posts is copied and pasted.
It is the result of my research, of my personal experience (I got my Indian driving license in 1975, US license in 1985, Netherlands license in 1986, Australian in 1992, and Singaporean in 1997), also the result of reading many books over the decades and websites. The English articulation, calculations and scientific/engineering advice is entirely my own!
Ram
all right! m extremely sorry for that!

but hey, you can still take my comment as a compliment!
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Old 10th July 2006, 13:19   #28
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Quote:
Originally Posted by Kaizer Sozay
Speedsatya
you have installed Hella Micro DE fog lamps whats the reprot on them?


i have Hella Micro DE fog lamps with 55w bulbs ...i got the entire wiring kit and 2 spare bulbs along witha 30 A relay .

about the light ,i dont need to use my headlights inside the city as the fog lamps are more then enough ..

i had tried using 100w bulbs in them and one of teh glass lens cracked due to the heat ...also the light was blinding other users ...so have reverted back to 55w bulbs ...
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Old 10th July 2006, 22:28   #29
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Quote:
Originally Posted by speedsatya
i have Hella Micro DE fog lamps with 55w bulbs ...i got the entire wiring kit and 2 spare bulbs along witha 30 A relay .

about the light ,i dont need to use my headlights inside the city as the fog lamps are more then enough ..

i had tried using 100w bulbs in them and one of teh glass lens cracked due to the heat ...also the light was blinding other users ...so have reverted back to 55w bulbs ...
Hey speedsatya did the wiring and relay come as a part of the kit?
and how much did you pay for the whole thing?
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Old 11th July 2006, 15:50   #30
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A small additional info, Yellow lights are for bad weather conditions, (read FOG) and Blue light are for use in Snow, as it cuts out the reflection.

Hope this helps.
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