Brighter Headlight Mod.

IronMonkeyL255 · Post by **IronMonkeyL255** » Fri Oct 29, 2004 8:57 pm

Has anyone here done it?

I was going to give it a try, since I happen to have 4 spare relays and a few inline fuse holders (salvaged from my recently removed security system).....

I suck at wiring, so I was wondering if anyone had a good how-to of how to hook everything up. I think I could do it if I could figure out how to hook everything up.

I already checked out Daniel Stern's website, and didn't see any really good pictures on there that I could use as a guide (there could have been some there, but my comp. doesn't like to show pictures sometimes).

While doing it, I could get some pictures and try to do a decent write-up.

vrg3?

vrg3 · Post by **vrg3** » Fri Oct 29, 2004 9:05 pm

Sure, I and a few other board members have done it. And car owners have been doing it for decades, so you might try doing a Google search for "headlight relays brighter" or something like that.

I would take pictures of my setup if I still had it, but I tore out my upgraded harness when I was having electrical problems.

It's really pretty simple once you think it through. I'd say the hardest part is actually figuring out a good place to mount the relays... I put 'em on the washer fluid tank. I epoxied little studs to the tank that the relays' mounting tabs could slip over. Then just route your wires. Subarus do use the switched-ground configuration that Daniel talks about, so use both sides of the circuit.

You can use quick-disconnect type crimp-on connectors to connect to the relays. At the alternator or positive battery terminal you'll want a 1/4" ring terminal, I think. And you'll probably use butt connectors to connect the 9004 bulb connector pigtail to your wires.

Be sure to fuse the circuit!

IronMonkeyL255 · Post by **IronMonkeyL255** » Fri Oct 29, 2004 9:58 pm

Wow...

Lots of info for regular, but I'm not seeing any for switched ground setups.....

How would these be different from a regular setup?

Here's a pretty good site I found to demonstrate: http://www.rowand.net/Shop/images/Headl ... iagram.jpg

Post by **Legacy777** » Sat Oct 30, 2004 12:22 am

Check out the headlight electrical diagrams

http://www.main.experiencetherave.com:8 ... g_(US).pdf

You can see that to complete the circuit it goes all the way through switch in the stock, etc. You could probably just rig up a set of relays for the ground side and see a difference.

You may want to take a voltage reading at the light vs at the battery, and see if you have much voltage drop on the positive side.

I plan on doing this, I'm just not sure how crazy I want to go. Because technically if you did both ground and 12v side, you would need 4 relays per headlight. That's crazy IMO.....I don't know if you could cut that down by combining lights or what....I don't know.....vikash may be able to shed a little more insight.

Also....since I'm anal....here's the canada headlight diagram

http://www.main.experiencetherave.com:8 ... g_(CA).pdf

mikec · Post by **mikec** » Sat Oct 30, 2004 12:37 am

Bloody DRLs.....

IronMonkeyL255 · Post by **IronMonkeyL255** » Sat Oct 30, 2004 1:29 am

Thanks for the diagrams, Legacy777.

Now to figure out what to make of it and where to put these in.......

I am pretty much planning to just do two relays, one for each side. I actually have a total of 4 good relays, so I could use all of them if I needed to.

I'm sort of curious as to how vrg3 hooked his up.......

vrg3 · Post by **vrg3** » Sat Oct 30, 2004 1:47 am

I just drew these out, so I haven't super thoroughly checked them, but they'll give you some idea how you might do this:

http://www.graphics.cornell.edu/~v/pics ... arness.pdf

Those are drawn with the idea that you cut the car's stock wires very close to the headlight connectors and splice your new cool stuff in. Ideally you'd actually replace the headlight connectors themselves, and you should, but there really is no such thing as a good 9004 connector, since by design it's got an inadequate base. But anyway... Hope that helps.

If you're doing this on a 92-94, you should get a pair of quality H4 bulb connectors rather than reusing the stock ones. I did this, and I also actually cannibalized a bulb in order to make a connector to plug into the stock harness, so I didn't have to cut any wires on my car.

IronMonkeyL255 · Post by **IronMonkeyL255** » Sat Oct 30, 2004 3:50 am

Thanks. That is REALLY useful. <- not sarcasm

I went out to try to get my hands on a few more parts, but Radio Shack was closed.......

Any reason you can't work with the H4 connectors on the '91? What exactly would you do with them?

I want to do this with as little cutting of the stock wiring as possible, so.......

Also, would there be any advantage to using only one headlight harness versus using both? It seems to me like it would be much simpler to use just one if you are mounting both relays in the same spot.

One other thing: any particular rating for the fuses off the power source? The relays are 30 amps, so would a 30 amp fuse work?

Sorry about all the questions, but I'm trying to get all the facts before I start on this.

vrg3 · Post by **vrg3** » Sat Oct 30, 2004 4:10 am

You can't use H4 connectors on a 90-91 because 90-91 cars use 9004 bulbs, not H4 bulbs.

If you want to do as little cutting as possible, try seeing if you can take apart an old 9004 bulb and turn it into a connector.

I think the reason Daniel Stern brought up the possibility of using both sides is that it gives you two common wires, one for each relay. Personally I chose to just split the one common wire on the driver's side, because I agree with you that it's simpler.

There's actually another method I'm going to try though, that I think might be kind of neat. Four relays, one for each filament. The relays could be mounted right at the lights. So then each pair of relays has one phat power wire and one phat ground, and aside from that is just plug-and-play between the harness and the bulb.

9004 bulbs have a 45-watt low beam and a 65-watt high beam, so a 15-amp fuse should be good for the low beams and a 20-amp fuse should be good for the high beams.

THAWA · Post by **THAWA** » Sat Oct 30, 2004 4:05 pm

I do believe rallylights.com sells 9004 pigtails

Post by **Legacy777** » Sat Oct 30, 2004 5:35 pm

vrg3, where did you get your upgraded H4 plug/connectors?

vrg3 · Post by **vrg3** » Sat Oct 30, 2004 5:45 pm

I was lucky and found some nice ceramic Bosch ones cheap on eBay. But at stock wattage (which I recommend sticking to in US-spec BC/BF lights) the more common thermoplastic types should be fine.

On my old Impreza I actually used the stock connectors. I cut the stock wire off of the contacts and soldered in my heavier wire.

tris91ricer · Post by **tris91ricer** » Mon Nov 01, 2004 7:11 am

Did Vikash just say 'phat'? Wow, our technical boy here, just said 'phat'...

Did you take a trip to the hood and back, V?

vrg3 · Post by **vrg3** » Mon Nov 01, 2004 2:30 pm

I often use the term phat to describe heavy-gauge wire. I don't know why.

IronMonkeyL255 · Post by **IronMonkeyL255** » Mon Nov 01, 2004 3:46 pm

I was poking around with mine and saw what you mean by taking apart an old 9004 bulb and turning it into a connector.

Can I find a 9004 connector at any autoparts store, or are they hard to find?

vrg3 · Post by **vrg3** » Mon Nov 01, 2004 3:53 pm

You should be able to find a connector that plugs into a 9004 bulb at any auto parts store. They generally have several inches of wire attached to them, and you attach your circuit to those. As with any other product, quality varies, but try to pick one that seems well-made and has thick wires coming off it.

It's hard to find connectors that plug in where a 9004 bulb would otherwise. Like Hardy says, Susquehanna Motorsports (rallylights.com) does carry them.

IronMonkeyL255 · Post by **IronMonkeyL255** » Mon Nov 01, 2004 4:23 pm

I'll just cannibalize a pair of bulbs for that.

vrg3 · Post by **vrg3** » Mon Nov 01, 2004 4:27 pm

Cool. If you could take some pictures of the hacking-apart process I'd be curious to see them... The 9004 base is plastic so I guess you'd do it with a hacksaw? When I did it with H4 bulbs I actually just used a torch and some pliers; everything was just soldered together.

IronMonkeyL255 · Post by **IronMonkeyL255** » Mon Nov 01, 2004 5:46 pm

No problem.

I actually just found an old 9004 LL bulb in the basement while I was looking for the multimeter.....

tris91ricer · Post by **tris91ricer** » Mon Nov 01, 2004 7:18 pm

So if our 92 bulbs are the same plug type as the H4s, does that mean we can use H4s in them, or what? What happens if i plug an H4 bulb in? will it get hot and explode? I know the bulbs on my 91s were 9004, but the 92s that were 9003 kinda surprised me..
i really just need to do the clear coating and sanding, first...

vrg3 · Post by **vrg3** » Mon Nov 01, 2004 7:22 pm

9003 bulbs, for all intents and purposes, are the same as H4 bulbs. So, yes, you can use H4s, and it will work just fine.

H4 is a European bulb designation. 9003 (or HB2) is an American designation. Technically, the 9003 specification is slightly more rigid than the H4 spec, but all H4s that are worth the glass they're made of would or do easily satisfy the 9003 requirements.

Brat4by4 · Post by **Brat4by4** » Wed Nov 03, 2004 4:44 pm

http://cgi.ebay.com/ebaymotors/ws/eBayI ... 7931845416

What the heck is this guy trying to sell? The bad engrish is throwing me off.

mikec · Post by **mikec** » Wed Nov 03, 2004 4:47 pm

I saw that yesterday, and had the same problem trying to decipher it.

I think its basically what is being discussed here. But I don't see how anyone could get away with charging over $150 retail as he claims. And I think the installation instructions are in the item decription

vrg3 · Post by **vrg3** » Wed Nov 03, 2004 4:53 pm

It looks like it might be a premade heavy-duty wiring harness for H4/9003 bulbs...

I don't like how they don't say what gauge the wires are. And why wouldn't they just use standard automotive relays, so that you can find a replacement when you need one?

Hopefully there's at least one fuse somewhere in that bundle.

What are the little thin green and black wires with ring terminals for? If they're for the high-current side of the circuit, that's absurd. If they're for the low-current side, this harness probably won't actually work with switched-ground cars.

mikec · Post by **mikec** » Wed Nov 03, 2004 5:18 pm

Yeah, looking at the picture again, the wire doesn't look very beefy.

Aren't those standard automotive relays at the bottom of the picture?

legacycentral bbs

A forum for 89-94 BC-BF(BJ) Legacy Owners and Fans

Brighter Headlight Mod.

Brighter Headlight Mod.