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Topic: Fog Light Upgrade (Read 1069 times) previous topic - next topic

Fog Light Upgrade

I actually did this about a month ago, but anyhow I decided to tell the story. I've had aftermarket fog lights in my air dam for a long time. They're Pilot PL-220C fog lights, which I think go well with 87-88 non-TC T-Birds, and it's a shame that they're not available anymore. They take standard H3 bulbs, and I've been happy with them.

Well, almost. They don't put out squat for light. They look good, but are in my opinion otherwise useless. So I decided to try to get at least something functional out of them. A good comparison would be my Explorer fog lights; those actually do something useful (*cough* shed light *cough). Fog lights should be useful.

First I did some re-mounting. I moved the lights way forward, and that didn't do anything. Then I moved them back to a middle position, and tilted them slightly outward so they match the profile of the nose. Still nothing.

I bought a pair of Sylvania Silverstar H3 bulbs, and put those in. If I stood outside the car I could at least tell that the fog lights were on when I looked at the street, but it was barely noticeable (read: useless).

So I went to the nuclear option. I bought a HID kit from retro-solutions. Now, I've read on quite a few sites that putting HID bulbs in non-HID housings is illegal, because the housings aren't designed for the HID bulbs and cause too much glare for oncoming drivers. I did a lot of research on this, trying to find out the exact issues behind it. I learned the following:

1. Halogen housings are designed for bulbs with a specific filament position. The point here is that most, if not indeed all, light housings are parabolic, and the filament is supposed to be at the parabola's focus. This ensures that the emitted light will be parallel, that is, not divergent. A filament that is too far forward or too far back will inevitably cause the light to diverge and create glare. The fact that HID bulbs don't generally have the filament at matching positions as halogen bulbs is the primary objection to putting HID bulbs in halogen housings. In fact, the DOT doesn't actually decree, "you can't put HID bulbs in halogen housings", they decree "you can't put bulbs in your housings that don't have matching filament positions". This actually makes good sense.

2. Light from the front of a vehicle, whether halogen or HID, has to meet certain luminosity requirements. Color temperature plays a big part, but it's more complex than that; what the DOT considers truly important is the overall spectral distribution. It should be even rather than comprised of narrow peaks that average to white light.

So having learned all this, here's the decision I made: I ordered the Digital HID kit with the H3 mini bulbs, at the stock 4300K color temperature. I'm not interested in that blue look the kiddies go for; the reason I did this in the first place was so I could see better, and 4300K is stock for a reason: the human eye is most sensitive to that wavelength. I don't know if bluer bulbs have less lumens, but they will *look* dimmer (as will anything they illuminate) simply because the eye isn't as sensitive to the light they produce. Moreover, the DOT considers anything over about 5100K to be unacceptable -- for the same reasons. So I went with near-stock light output. Silverstars put out 4000K light, so these are very close. As for the H3 minis, that's all that were available, but it turned out to be very fortuitous as you'll see below.

When I received the kit, I found that the bulbs were adjustable, with the default filament position 1mm nearer to the rear of the housing than for the Silverstar bulbs. I was able to move the HID bulbs forward by 1mm until the filament position was the same with respect to the bulb's stop ring. The bulbs themselves, from a size standpoint, are a very close match to stock bulbs, though they are about 2mm shorter. Correct placement of the filament position is what's really critical, though, and I spent a lot of time making sure that they were correct to within the thickness of the filament itself.

The fog lights have shields built in so that no light is supposed to escape above horizontal. I did my best to make sure they were oriented correctly, which is something we're supposed to do regardless of the bulbs inside. However, with something as bright as HID's, it's especially important to get it right. I'm satisfied that they're not pointing too far up, though I think my driver's side is pointing just a bit too far down. I need to revisit it.

As for the ballasts, it was a really enjoyable project, and the TC header panel turned out to be a godsend. The wires to the housings are only about a-foot-and-a-half long, but the optimal mounting position turned out to be the horizontal crossbrace behind the bird emblem. Each ballast has two mounting screws. I had to drill one hole in the crossbrace on each side, and I reused the mounting screws for the crossbrace itself for the second screw. I had to use some nylon spacers on the crossbrace's original mounting screws because they're a little too wide to fit on the ballasts, but it wasn't much of a problem.

Okay, pictures:

The first one has the car off, and I had just turned the headlights on. It's normal for HID's to appear blue until they warm up, which takes about 30 seconds. The passenger side one was buzzing, not wanting to turn on until I actually started the car. My guess is that the ballast needs a substantial amount of "turn-on" current, though when fully on they consume less power than stock lights. This would be a good point to note that I got the normal 35W kit, and from what I've seen, the new 55W kits would be WAY too bright.

The second picture is about 30 seconds later, with the car running. The fog lights are very close to the stock color now.

The third picture is about a minute after I turned on the lights.

The fourth picture is looking forward, of course. The fog light pattern is clearly visible, though it cuts off well before the headlight pattern -- as it should. Actually, my headlights are out of adjustment -- they're pointing way too far down.

I'm very happy with them, though I should point out that my digital camera makes the light from both the headlights and fog lights appear a little whiter than they actually are in person. My headlights are Sylvania 9004LL bulbs. I'm thinking that if I switched them to Silverstars they would be, from a color standpoint, indistinguishable from the fog lights. When one burns out I might buy a pair and see.
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5.0L Speed density
Explorer intake
'92 Mustang GT cam
GT-40 racing heads
Unequal length headers
Custom-made duals
19# injectors
65mm TB
AFPR
T/C header panel
11" brake upgrade
T/C rear sway bar
Electrical mods: too many to list :D

Fog Light Upgrade

Reply #1
Pic #4...
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5.0L Speed density
Explorer intake
'92 Mustang GT cam
GT-40 racing heads
Unequal length headers
Custom-made duals
19# injectors
65mm TB
AFPR
T/C header panel
11" brake upgrade
T/C rear sway bar
Electrical mods: too many to list :D

Fog Light Upgrade

Reply #2
Was fitting the bulb into the housing a problem?
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
#2 (right): DD, power everything (sorta)
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Fog Light Upgrade

Reply #3
Quote from: t3skidoo;281999
Was fitting the bulb into the housing a problem?

Mainly in the sense that H3 bulbs in general are a PITA to install; H3 bulbs have a metal stop ring, a notch that fits into a retainer tab at the top, and a retainer screw at the bottom. This is true whether you're dealing with halogen or HID bulbs; it's part of the H3 form factor. The retainer notch on the HID bulb didn't want to fit under the retainer tab on the housing, and it took some fiddling. However, I had the same problem with the Silverstars, so it might be that the tab on the housings had been cut just a fraction of a millimeter too wide for the standard H3 form factor. It wasn't anything I couldn't solve with a small pair of needle-nose pliers.

The H3 mini HID bulbs have a rectangular base rather than a round one, and the squared-off corners didn't want to fit through the hole (square-peg-in-a-round-hole problem). A simple solution was to take a fat blade screwdriver, stick it in the housing, and push it against the entry hole while turning it to widen the hole by just a tiny amount (fraction of a millimeter). That was enough to let me work the bulbs in.

Full H3 HID bulbs probably would have been too long to fit in the housing without hitting the internal light shield, but H3 mini bulbs are ~2mm shorter than standard bulbs, so length wasn't a problem.
[SIGPIC][/SIGPIC]
5.0L Speed density
Explorer intake
'92 Mustang GT cam
GT-40 racing heads
Unequal length headers
Custom-made duals
19# injectors
65mm TB
AFPR
T/C header panel
11" brake upgrade
T/C rear sway bar
Electrical mods: too many to list :D

Fog Light Upgrade

Reply #4
Your turn on problem can probably be solved by installing a relay before each ballast. If you are using a factory TC switch this is def a good idea because all of the current for the fog lights travel through the switch(no stock fog light relay).

Fog Light Upgrade

Reply #5
Thanks for the tip. I'll definitely give that a try. I've got plenty of spare relays, so it won't be a hard thing to do. I just need to finish my speed control mod first, which is slowly driving me crazy (I have it mainly working, but I need to smooth the output so the light doesn't flicker -- I'll tell that story in the speed control mod thread at some point).

Here is a picture that shows where I put the ballasts. They're waterproof, but where they are they're also covered by the header panel. It's not visible in this picture, but below I have all the wiring tied off with zip ties.
[SIGPIC][/SIGPIC]
5.0L Speed density
Explorer intake
'92 Mustang GT cam
GT-40 racing heads
Unequal length headers
Custom-made duals
19# injectors
65mm TB
AFPR
T/C header panel
11" brake upgrade
T/C rear sway bar
Electrical mods: too many to list :D

Fog Light Upgrade

Reply #6
Quote from: kendoo130;282007
Your turn on problem can probably be solved by installing a relay before each ballast. If you are using a factory TC switch this is def a good idea because all of the current for the fog lights travel through the switch(no stock fog light relay).


I put a relay after the stock fog light switch and I'm pulling power from before it hits the headlight switch. That did the trick. Thanks!
[SIGPIC][/SIGPIC]
5.0L Speed density
Explorer intake
'92 Mustang GT cam
GT-40 racing heads
Unequal length headers
Custom-made duals
19# injectors
65mm TB
AFPR
T/C header panel
11" brake upgrade
T/C rear sway bar
Electrical mods: too many to list :D

Fog Light Upgrade

Reply #7
For foglights, HID or not will make little difference with glare as the stock lights glare horribly to begin with. With HID, you're just glaring with 50% more light (6k lumens rather than 4k). Also halogen's color temperature actually cuts through moisture (to our eyes) much better than HID's. While I have retrofitted HID projectors in my headlights, I won't touch the foglights even if I were offered the parts for free.

I hope to find your experience on the ballasts/ignitors here in a couple years as non-OEM ones are known to quit working within a couple years. It would be good to know of a reliable aftermarket source.
1988 Thunderbird Sport

Fog Light Upgrade

Reply #8
I think you're right about the headlights. A couple of days ago I adjusted my headlights and fog lights, and I could see how the headlights would produce glare no matter what I did, and I have stock halogens in them. HID's would make it a whole lot worse. It looks like the "HID problem" is really a matter of the HID amplifying the inherent problems in the halogen housings. I found that the beam pattern from my fog lights was way more precise, with a much sharper cutoff. As for the longevity, I guess only time will tell.
[SIGPIC][/SIGPIC]
5.0L Speed density
Explorer intake
'92 Mustang GT cam
GT-40 racing heads
Unequal length headers
Custom-made duals
19# injectors
65mm TB
AFPR
T/C header panel
11" brake upgrade
T/C rear sway bar
Electrical mods: too many to list :D