I've heard from many main dealers hid's are illegal to have without headlamp washers
Just saying. Still going to get mine done like
How high can you go without melting your headlamp
?
Do you mean colour temperature? Because if so, you need to understand that COLOUR temperature has nowt to do with ACTUAL temperature.
HID's run cooler than halogens, since they only draw 35W most of which is converted to light. A standard halogen will draw 55W, a good part of which is converted to heat
As regards colour temperature, 4300K to 5000K are regarded as nearest to natural daylight, and produce the most USABLE light. 4300K are what most OE lights have fitted and are by far the brightest. As you move UP the colour temperature scale, the amount of USABLE light decreases. there isn't much in it at 5000K, (you'd need technical measuring stuff to see it), but by the time you get to 6000K you have lost some usable light.
8000K, 10,000K and 12,000 K are so blue they are best kept for the concourse.
http://www.mydepots.com/page.html?id=24
You need to be careful on two points: first off, always use HID burners (bulbs) in PAIRS. If you have slightly different colours, it increases the chance of a pull from Plod. This might sound obvious, but if you buy an aftermarket set, then a burner goes out, can you be SURE to get the correct colour temperature as a replacement?
Secondly, just like in Halogen, buying top quality bulbs pays. Philips are about the best, but cheap Far Eastern knock-offs can be quite poor. Some were measured at only 790 Lumens, (light output) so less than a decent halogen.........
Jamie: The Scottish thing was me trying to have a laugh at the two early posters, both of whom were Scots, which I found coincidental. No offence to any Scots living or dead was meant.