Heat from Fog Light. Is this normal?

[Chuck W.]

I installed LED lights in my litronic headlights a couple of years ago. I decided to put the halogen back in. I have a variety of bulbs and installed an H7 55 watt bulb. The lens of the headlight heats up quickly and the lens is hot, very hot, to the touch. I bought another H7 55 watt bulb (GP Thunder 8500K) and have the same result, a very hot lens. My concern is if I leave the fog lights on with this heat I will melt the lens. It is that hot.

What am I missing here? TIA

[Nine8Six]

Hey Chuck

I could be wrong of course. Your lens material is some wicked high quality polycarbonate (super strong, but flexible?!). Nothing compared to the Chinese polycarbonate I've seen not long ago.... although both are made out of the same chem properties, some seems better than others

For info that stuff is designed to sustain 300°F (150°C). I'd like to believe that your Porsche lens falls into this range! I'd say get a temp reading off the top of the lens. If you exceed 250F then it might not much melt it but certainly it will discolor or deform with time :/

[BruceH]

The halogens do get very hot. In the DRL threads that suggest using the fogs for the DRL, the consensus seems to be to use LED's instead of halogens to prevent discoloring the lens. Occasional use should not be a problem since that is the way Porsche designed them.

[Nine8Six]

oops did I say sustain, maybe not the proper term. Think it melts at that temp. Not sure. For someone else to try

[particlewave]

Yes, it is normal.
No, it won't melt the lens.
Yes, it will discolor the lens (yellowish brown) if used frequently and for extended periods of time.

[Chuck W.]

Thanks for the responses. I'll go back to the LEDs. It is not worth the risk of discoloring the lens.