Fitting 100/80w headlight bulbs - legacylad
Following the sale of my (surplus) Legacy, my only transport is a 1997 VW Transporter, and having relocated to rural North Yorks a lot of my driving is on unlit moorland roads with the occasional wandering sheep. I have always found the standard bulbs feeble for such driving, (previously I always drove the Subaru at night) and have just bought some 100/80W H4 bulbs for improved forward vision. Many of the wagon drivers in my part of the world fit several spots on top of their cabs, effective but not what I want.
Such bulbs have been fitted on previous vehicles over the years, without any problems, but not fitted in this van! I do not want to 'fry' the wiring, so prior to fitting, what, if any, electrical mods should I make?
p.s. I realise they are illegal for on road use, and even if I wanted to, I could not drive fast in my van on these roads, but the improved illumination would be a beneficial safety factor IMHO.
Fitting 100/80w headlight bulbs - Peter D
Read this tread.

Regards Peter
Fitting 100/80w headlight bulbs - George Porge
Fitting the bulbs only will overload the wiring, you'll need to uprate the loom with relays etc.

Check the voltage at the bulbs with the engine running and compare the readings with the voltage at the battery again with the engine running, if there's a large difference then uprating the loom and using the original bulbs will make a huge difference.

My MK2 Golf was 2.5V down at the bulbs, the uprated loom I fitted made a huge difference even with standard bulbs, (the light was much whiter compared with the original browny colour), 80 / 100s were fantastic. ;o)

The kits are around £60 for FWD VWs, so compares favourably with adding spots. :o)
Fitting 100/80w headlight bulbs - George Porge

Might be worth a look around here, they've their own forum too
Fitting 100/80w headlight bulbs - Ruperts Trooper
Jut use one of the "30-50% brighter" bulbs currently available as LEGAL replacements. There's plenty of choice, particularly in H4.
Fitting 100/80w headlight bulbs - kithmo
Why not just fit a couple of spots on the bumper or in the grill, then if wired correctly using relays there would be no extra load on the existing wiring and you would still be road legal.
Fitting 100/80w headlight bulbs - BobG
Fitted some to my 1966 Land-Rover. No great difference in light output just poor beam definition on dipped - even with short wires and relays. Much better with premium branded "+50% with xenon" type bulbs especially in fog where the sharp definition on the dipped prevents glare and dazzle to both other road users and myself.
Fitting 100/80w headlight bulbs - Roly93
I think the main problem with fitting high wattage bulbs comes if you have polycarbonate headlamp lenses. They can cause yellowing of these lenses over a period of time.
Fitting 100/80w headlight bulbs - George Porge
No Roly93, the main problem is overloading the already overworked VW wiring loom and setting it on fire
Fitting 100/80w headlight bulbs - jc2
Fitting 100/80w headlight bulbs - Clanger
Any uprated bulb of the same wattage should be a good stating point provided your reflectors are in good order and the lenses spotless. Start with the basics.
Stranger in a strange land
Fitting 100/80w headlight bulbs - Doc
>.> I realise they are illegal for on road use, >>

It is a popular misconception that 100w bulbs are illegal.
There is a minimum standard in the lighting Regs. but no maximum.

Fitting 100/80w headlight bulbs - yorkiebar
Sorry, but there is a maximum legal wattage !
Fitting 100/80w headlight bulbs - psi
Statutory Instrument 1989 No. 1796
The Road Vehicles Lighting Regulations 1989

5. Markings-

(a) Any vehicle not covered by sub-paragraph (b), (c) or (d): An approval mark or a British Standard mark

8. Wattage-

(a) A motor vehicle with four or more wheels first used on or after 1st April 1986: No requirement

(c) A motor vehicle with four or more wheels first used before 1st April 1986: 30 watts minimum
Fitting 100/80w headlight bulbs - Doc
Sorry, but there is a maximum legal wattage !

Can you point me to the relevant Regulation?

Fitting 100/80w headlight bulbs - Hamsafar
When I bought some 130/90w H4s about 12-13 years ago, they said "Not for use on vehicles first used before 21st October 198?". It was a 1986 car, and I remember it being borderline. They must have thought there was some prohibition. Is it to do with E approval?
Fitting 100/80w headlight bulbs - psi
Highway code vaguely covers "high output" lamps:

94: You MUST NOT

* use any lights in a way which would dazzle or cause discomfort to other road users

Ask Honest John

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