Thread: LED H4 headlight bulbs - are they any good?

Originally Posted by Tank

Isn't it illegal to run 100W in headlights, it might be bright enough for you, but have a thought for oncoming traffic, Regards Frank.

Honestly not sure of the legality of 100w high beams but they are available at auto stores and auto sparkies, even seen 130/130w bulbs too. The level of light for oncoming traffic has little to do with the brightness of the lights but more the angle I think. after all some of these newer cars with hid lights are far brighter than a 100w high beam when on low and coming towards you - you flash them and they turn their highs on to show they are on low, mostly seems to be the jap fourbies like the cruiser etc.

Originally Posted by superquag

SSSHHhhh Frank,,, - the 100W low beams are cooking the insides of his fittings, building up a film inside the lens-glass, and on the reflector. Pretty soon his light output will be less than a clean 'normal' wattage headlamp in good condition... But the scatter will make them appear brighter.

Eventually, the glare from this film might interest the gendarmes....

Never heard of this issue with them - why would higher wattage beams make any difference - I could just run them dipped to high the whole time!

Originally Posted by pfillery

Never heard of this issue with them - why would higher wattage beams make any difference - I could just run them dipped to high the whole time!

With halogen bulbs, over 95% of the energy from the power they use is converted to heat. So if you double the power, you double the rate of heat production. Whether this will have any detrimental effects will depend on the amount of cooling available and the construction of the light assembly.

Provided that the reflector and lens are entirely of metal and glass, there should be no issues. But I have an idea that the metal reflectors usually have a very thin protective film of some type of plastic. In addition, there is almost always some communication between the interior of the light and the seal round the bulb, and invariably a seal of some type of organic material between the reflector and the lens.

In designing the lamp assembly, the manufacturers have found that with the designed bulb wattage, there is no problem with any of these various organic materials decomposing or vaporising. However, if the amount of heat produced is increased, say from 55w to 100w or even 130w, this will result in a temperature rise well beyond anything the manufacturer has tested and approved. At these temperatures it is likely that some of these organic compounds will either decompose or vaporise, with at least some of the vapour going into the cavity of the assembly. It will then deposit on the cooler parts of the assembly, typically parts of the reflector or the inside of the lens.

Whether this will actually happen, I don't know, but this is the mechanism by which it certainly could happen.

I always found when driving trucks interstate that you could tell the non standard lights from the standard, they seemed to be much more glare in the eyes of the driver sitting in the higher position in a truck. yet these same lights were bearable when driving a car. I always wondered if these (at the time) high powered lights had ever been tested, on the road, from a truck drivers perspective, and I would think these new HID lights available now would cause the same problem to truck drivers today, Regards Frank

I used to have a 130/90 in one headlamp and a 60/55 in the other, to see if I could spot the difference. Nope. I think by the time you factor in voltage loss and thicker filaments there is little gain except in heat produced. When the 130/90 died I just went to the first of the plus 30's, I don't think the plus globes are all that dear now.

http://www.ebay.com.au/itm/HEADLIGHT...item2568d367c2