HK G36C

Good write up! Thank you

porsche42

great write up thx. Looks like upgrade worth doing.

LexVan

Very nice write-up.

I had the opposite issue with my 2016 Ford Explorer. The headlights are a nice clean white HID & LED light, but the fogs, by comparison, were yellow. Looked silly. Swaped in LED fog light bulbs, 15 minutes. Nice color match.

Pitocin

If the car uses the D3S bulb then it should work just as well. I can't imagine it used a different bulb though.

I had some more nighttime driving and I'm VERY pleased with the results. I pulled up to an Audi with full LED headlights and the light output and tint was very comparable. A quick search reveals they use LEDs that produce light at 5500k which they claim is the closest tint to daylight.

laranja

Good write up - photos really show the difference well.

and btw, WHAT a user name!

LTP

ok thanks Pitocin.

LTP

hey Pitocin, just want to make sure this is what you got


Thanks

Pitocin

That's the correct bulb.

Apparently a lot of counterfeits are out there so make sure you verify your bulbs are legit. I had no problem from that Amazon listing but it's always good to verify.

http://trust.osram.info/appsinfo/trust/frontend/trust.do?locale=en_US

LTP

thanks Pitocin, with the new bulb, does the HID color and intencity matches or much closer to the DRL in person?

Noah Fect

So, I just finished making this mod on my PDLS-equipped 981BS. I took the same approach that Pitocin did, doing the driver's-side headlight first and cruising around a bit to evaluate the difference. Major props to Pitocin for doing the homework and sharing the results.

The difference is definitely more qualitative than quantitative. You don't get a dramatic increase in illumination but I do think there's some contrast improvement, depending on what you're looking at. There's certainly no downside -- the xenons looked good before and they look great now. It's a cheap cure for LED envy.

The slight change in apparent brightness won't be a problem for other drivers, and the color temperature match with the DRLs is much nicer. The transition between high and low beam color temperature seems to be a better match as well but I'm not sure how valid that observation is, it's more of a vague impression.

Overall I wouldn't call it a "gotta-have-it" upgrade, but I'd say it's worth swapping out your 66340HBIs for the 66340CBIs if you don't have any other plans for the $150 it'll cost. It's a no-brainer if you need to replace a burned-out bulb, though. Install a pair of 66340CBIs at that time, or have your service tech do it.

One caution is that it's not quite as easy to R&R the headlight assemblies as people are making it sound (referring to both Pitocin and Plenum, whose post was extremely helpful as well, along with Schnell's blog). Good work lighting is required to see how to reinstall them, and having a second person available to hold the assemblies away from the paintwork as you fiddle with the wiring harness is helpful as well. You need to follow the suggestion in the shop manual re: leaving the handle of the wrench at 90 degrees after removing the headlight assembly:



Otherwise it may be hard to shove the headlights all the way into place even when they're oriented properly.

Most important of all: when reinstalling, make sure you turn the socket wrench tool all the way to its end stop, marked by a loud and somewhat unnerving click. If you don't hear the click, then you could end up in the same situation that some 991TT customers found themselves in when somebody in the factory didn't get that particular memo, as well as one or two people with aftermarket wraps. PDLS is damned expensive -- and you'll see why when you get your hands on the hardware -- so be careful.

LTP

yes thx Pitocin for the write up, the color tone is much closer if not almost the same as DRL.

charles06

Food for thought:

The whiter the light output is, the worse it is for inclement weather. This is why fog lights tend to be on the yellow side. Better in fog... Also why cars run yellow headlights in the 24-hour races when raining. Years ago, when living in OH, I changed to a whiter bulb on one of my vehicles. Total nightmare in a rain/snow storm. But my aftermarket, yellow fog lights were awesome.

Noah Fect

Edit: actually the strongest line is near 6100K, going by the usual Wien black-body approximation. But the spectrum has enough content at "daylight" wavelengths that it looks warmer than a lot of 6000K sources:



The LED DRLs on the 981s and presumably 991s look like the usual cool-white 6600K LED spectrum with a 440-nm peak:



So while the 66340CBIs look good next to the DRLs, they're still somewhat warmer.

Kicking myself now for not measuring the 66340HBIs before I pulled them out of the car, that would've been interesting.

LTP

for sure yellow provide visibility penetration in poor weather condition, luckily Hong Kong doesn't snow or fog.

charles06

Interesting read here....

http://www.danielsternlighting.com/t...ght_color.html