I just switched my OEM D4S bulbs to 6000K. I'm happy with how it looked from the outside as it matched the LED parking lights I have in the high beam light assembly. However, it doesn't illuminate the road quite well.

I do know that the higher the number (the bluer the light), the less lumens there is. I have 6000K HID in 3 of my BMWs (all in H1 form) and D2S 6000K HID in my Porsche and they all light up the road very well and I am very used to the 6000K color. I checked the box and it did indicate 6000K and these were bought the same time and from the same vendor as the D2S for my Porsche. I didn't see any noticeable deterioration in lumens when I switched from the OEM D2S to 6000K D2S in my Porsche. I just don't know why the result is so different in my 3GS. Is it due to a different design of the Lexus projectors? Or is it due to a different characteristic of the D4S against D2S and H1?

And I've seen people here with up to 8000K in their HIDs. Maybe I'll just switch to 5000K to get some of the light back. Any ideas?

 

Well, GS does not have the best projectors IMHO. And also, D4S bulbs are slightly different from D2S/R bulbs. They are mercury free, and use less power. Which is why the output is noticeably lower

 

sniip3r pointed out some of the points already.

first of all, h1 i don't believe is oem hid spec, that's more like hid kits. they are not valid since the optics are messed up and a lot of times you get glare on the road than rear clean projection / reflection.

comparing oem spec, d2s are the older type with mercury, noticeably better light output.

d4s is what lexus use now, indeed, light output is quite a bit less

 

good answer sniip3r and romini !!!

 

It is the reason I don't switch my D4S to 6000K because I am afraid to lose the road illumination.

 

Thank you for the informative answers. So I guess it is both the GS projectors and the D4S characteristics that contributed to the significant light reduction that I've noted.

BTW, rominl, the H1 HID kits that I used were all for my BMWs with projector housings with very clean cut-offs. I would like to note that I make sure any HID kits I use doesn't blind other people on the road because I really don't like those ignorants who do. Therefore, the investment in more expensive projector assemblies and projector conversions in those cars.

So, do you guys think going to 5000K would yield a good balance of light output and match the LED park lights as well? Or, maybe switching out the 35W ballasts with a 50W HID kit?

 

I think its partly the bulb you have too. People who use the Philips Ultinon 6000K report much more light output than those using Garax or even PIAA. I have heard this here, but also from people on the Benz forum.

Problem is the Ultinon Flash White bulb set is $395 so you really pay to play. Alternative is to go back to 4300K if you care about brightness.

 

I think I'll just put the OEMs back. The 6000Ks are unsafe and they have to go.