Twin 40's braaaaap
Join Date: Jun 2009
Location: United Kingdom
Guys, word of advice from someone who is an LED specialist in lighting;
The quantity of LEDs is irrelivant - different LED manufacturers have different luminous outputs.
the wattage of the LED unit is irrelivant - wattage is a measure of power consumption, not light emitted. A bad LED might have a lower lumen per watt efficacy eg 10lumens for 1 watt, vs a good one at 100 lumens for 1 watt. As the power consumption of lighting on a car is not an issue (unlike your home etc...) the low power of an LED is a pointless exercise.
The light beam spread must be close to a conventional lamp, as the reflector housing has been designed around the centre point of the origenal lamp. An LED alternative cannot match this, so the refelctor will not be as efficient, so will loose levels of efficiency - eg the LED version will need to generaly need to output more lumens than an conventional lamp, just to achieve the same percieved output on the outside of the car (known as the luminaire lumens).
Colour temperature - Cheap LED manufacturers may not have tight tolerence control of their LEDs, so one light might appear a slightly differennt colour to the other (Hella had this issue on the recent A4's headlights).
So unless you are doing this for the following reasons, its going to be a case of trial and error & pointless expense in swapping over to LED lamps;
Improve drivers reaction time behind you.
match sidelights to Xenon colour temperature
your vain & doing this for no other reason than to............
I know my shi2 when it comes to LEDs & lighting. The majority of suppliers on ebay etc... dont provide you with enough information to be able to make qualified decisions as to wether these will be truly suitable.
But if you insist on doing this, go to lucus or some such website, find out the Lamp lumen output of the patrticular lamp you are looking to replace, & make sure that the LED lamp you are buying at the very least states the lumen output, (which would need to be 10-20% more than a lucas lamp, to ensure the reflector losses are allowed for.
Thats my 2 penith worth.
1971 Alfa GT1300 Junior - Red
1988 Alfa 75 3.0 V6 America
1989 Alfa 75 3.0 V6 Veloce - totalled by the Mrs, slowly being stripped.