View Full Version : H4 Foglight Upgrade

10-06-2010, 08:53 PM
I am enjoying my massive fog lights from a 93 GTS. I want H4's in there so I am upgrading the harnesses to handle the brighter setup. Anyone attempted this before I step into fun on my own? I know fuses will need to be swapped in as well.

10-06-2010, 10:48 PM
You want to put a dual-filament (high/low) bulb into your fog lights?

You realize an H7 is a 55W draw, and a more efficient, modern design than the H4, which also draws 55W (on low, anyway)? Might be rather more effective to drop in a set of bulbs along the lines of Philips X-treme Vision, 100% more light output to the road (improved efficiency and geometry) and actually longer life than standard H7.

10-06-2010, 10:58 PM
It would be kind of fun putting in a dual filament bulb and have the high setup where both sets go to high. I have been spending a lot of time driving solo in the mountains at night, so extra visibility is appreciated.

I want to install something along the same brightness and take advantage of the oversized fog housing. The bulbs would be the Nokya Yellows that match my current H4 converted headlights.

10-07-2010, 05:41 AM
If you're looking for more light output, going from an H7 to an H4 is likely to disappoint.

An H4 produces 1000 lumens on low beam, 1650 on high. An H7 produces 1450 lumens. However, these are standard numbers, not covering high or ultra-high efficiency bulbs. The best H4 top out at 1900 lumens on high beam, while the best H7 (+65) reach 2100 lumens.

---------- Post added at 09:41 PM ---------- Previous post was at 09:37 PM ----------

And seconds after I post, I realized that even the 93 fogs were H3, not H7.

That said, a 55W H3 is 1450 lumens as well, and there are ultra-high-plus efficiency versions available. Not to mention the 100W versions, though those have issues with plastic housings.

10-07-2010, 06:49 PM
So, I actually did some research on size, focal point, wattage, and lumens.

The thing I hate about HIDs is that they are not auto leveling unless you make them that way. Every aftermarket HID headlamp I see on the road blinds me, and I hate the spectrums typically available.

Obviously the H4 isn't available in the US. I guess I could have titled this thread "Dual-Filament Foglight Upgrade". Brighter doesn't necessarily mean more lumens, it could just be a better placed bulb within the lamp. I would love to have a 2100 lumen output when I am driving at night, but something lower for daytime running.

I know the lights aren't dimmable. I could do something similar to the knockoff H4 conversion headlamps with the "city light" socket. The dual filament setup is appealing, because that circuit is relatively easy to replicate, and I can use a stock Toyota relay.

10-07-2010, 07:19 PM
They blind you because people are putting HIDs in halogen housings and the reflectors are designed wrong for HIDs.

10-07-2010, 09:51 PM
^ That too.