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OHSCrifle
OHSCrifle UltraDork
2/25/23 11:39 p.m.

I have a couple cars with dismal headlights. They could certainly use a lens polishing but entire replacement headlamps are not terribly costly at RA. What I'm curious about is I've seen people discuss adding relays so a more substantial wire can be used to power the lights - because the normal wire is generally kinda skimpy.

Is there a kit available for this kind of relay modification?

 

if it matters:

2015 Mazda6 touring

2012 Toyota highlander base

Nockenwelle
Nockenwelle New Reader
2/26/23 12:40 a.m.

You don't need a kit. General-purpose 12VDC cube-style relays, inline fuse holders, a spool or two of wire, and a handfull of crimp connectors is all you need. If you can operate terminal crimpers, wire strippers, and zip ties, you are qualified for a DIY version. The general idea is to use the factory circuit(s) to trigger relays feeding battery-sourced and fused power directly to the bulbs.

I refuse to accept crap headlights on anything I own. All the cars that have incandescent bulbs get relays and a wiring upgrade like you are looking at. Being able to see at night is not only nice, it's a legitimate safety feature. Being able to pick out skunks crossing the road 1/4 mile or more out is a bonus.

The OEMs size the wire for adequacy based on current rating (temperature limit) and cost. None of them except the Germans seem to appreciate that voltage drop is critical: when you only have 12 or 13 volts to work with, all of them are important. Incandescent bulb output is exponentially proportional to the voltage (~V^3.4), so the problem is even more evident.

codrus (Forum Supporter)
codrus (Forum Supporter) PowerDork
2/26/23 12:46 a.m.

IME a lot of cheap aftermarket replacement headlight housings are crap.  I'd go for polishing (and then UV-coating) OEM headlights over replacing with aftermarket.

 

preach (dudeist priest)
preach (dudeist priest) SuperDork
2/26/23 6:56 a.m.

I replaced my OE globes on my Tacoma with aftermarket and LEDs. It came out fantastic with the exception of wet snow not melting off of the globes due to lack of heat from the bulbs.

I also replaced my 7" sealed beam round lights on my Opel with aftermarket 7" LEDs. HUGE difference. I know that will not work on your applications though.

Seems aftermarket globes are a roll of the dice. I did OK on the Toy but they are plastic lenses. I know a guy at work that replaced his mk4 GTIs globes and was surprised that they were actual glass. I have seen some, mostly projector type, that you'd be better off strapping old school 2 D-cell flashlights to your hood and see better.

02Pilot
02Pilot PowerDork
2/26/23 7:01 a.m.
codrus (Forum Supporter) said:

IME a lot of cheap aftermarket replacement headlight housings are crap.  I'd go for polishing (and then UV-coating) OEM headlights over replacing with aftermarket.

This. The factory housings are the way to go in most cases. When I got my Volvo, the headlights were blasted from 17 years and 200k miles. Based on the Project Farm recommendation, I bought this Sylvania kit and was very pleased with the outcome. I opted to use a random-orbital polisher after trying to do it by hand, but yours may not need such extreme measures.

Adding relays is definitely the way to go on the electrical side. Hella makes relays that have an integrated holder for a blade fuse right on the housing.

Caperix
Caperix Reader
2/26/23 7:27 a.m.

If you can separate the lenses from the housing, many just need some time in the oven to soften the glue.  The are some very good bixenon projectors that can be installed.  The retrofit source is a good source of some quality aftermarket lights & parts to perform your own conversion.

ddavidv
ddavidv UltimaDork
2/26/23 7:34 a.m.

How we solved crappy headlamps in the 1980s.

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
2/26/23 9:02 a.m.

Relaying or brighter bulbs just give you crappy lighting, but brighter.

mad_machine
mad_machine MegaDork
2/26/23 9:14 a.m.

crap headlights on other people's cars makes my evening commute a nightmare.  I get blinded by at least 5 cars a night running with their highbeams on. These people leave them on no matter how many or how often other cars flash them. It is the same cars every night.  The worst part is, we have excellant street lighting here, it's not even dark.

It's enough to make you want to follow them home and rip out the wires that power the highs.

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
2/26/23 9:18 a.m.

In reply to mad_machine :

it may not be the high beams.

i worked with someone who recommended a certain kind of bulb,  but the downside of them was that they were so bright that the high beams were dimmer, so you had to upgrade the high beams too.

I asked him point-blank if he realized how much of an shiny happy person he was for driving with lights brighter than high beams, and his only response was "yeah but i want to see"

 

 

84FSP
84FSP UberDork
2/26/23 9:29 a.m.

After sorting out the headlight lenses do a bit of research on the LED drop in headlights.  I've had good luck with the Hikari brand as they have an adjustable bean that helps match to the headlight style a bit better.  The LED upgrade was even better than the oem HID on my Caddy.  They really helped out on my rabbit as well.

wake74
wake74 Reader
2/26/23 9:46 a.m.

Timely topic, as I need to do something with my 15 year old Tundra DD + tow pig.  I polished them up with my obirtal and they came out great, but then faded again quickly.  Is there a preferred coating?

RockAuto sells dozens of replacement bulbs, some of which are marked as "brighter".  Any bulb preferences for those not looking to go the relay, new wiring route?

We recently bought the Mrs. a 2 year old CPO Macan with the PDLS+ option. Driving the Tundra is like holding a candle out the window by comparison.

rslifkin
rslifkin UberDork
2/26/23 10:00 a.m.

Personally, I've never had good luck with polishing housings and keeping them clear.  It always turns into a "polish every few months" activity. 

Plenty of cars have just generally crap headlights.  Depending on the housings, there are a few options.  If they take H4 bulbs and the housings can handle some extra heat (and have a decent beam pattern), you can upgrade the wiring and run higher wattage bulbs.  For high beams that use a 9005 bulb, swap to a 9011 HIR bulb with slightly modified tabs so it fits.  They're optically compatible in high beam use and the 9011 is a bit brighter. 

Other options are a projector retrofit (generally the best route to good low beams).  And you can always add driving lights to supplement high beams. 

I'm no fan of stock headlights in most cars.  At this point, SWMBO's Prius is the only thing in our fleet with stock lights, and that's only because it's on the chopping block for replacement (so not worth upgrading even though the headlights are awful). 

The E38 has 9011s in the high beam spots, and I also swapped the stock Bosch low beam projectors for bi-xenon ones (currently it has Mini H1 7.0s in there, but I'd love to upgrade to the Micro D2S 5.0 that came out later on). 

The Jeep has the glass lens Euro housings (much better beam pattern) with 100/80 watt H4 bulbs in there, which gives pretty good low beams.  And then a pair of driving pattern Hella 4000s on the bumper with 100w bulbs, and a pair of IPF 968s with 100w bulbs outboard of those and aimed outward slightly to give more light along the sides of the road for wildlife.  The lights on the bumper all trigger with the high beams, so the high beam switch delivers 600 watts of halogen in old school form. 

In my mind, low beams definitely reach a point of "good enough" where more light isn't really useful, a good beam pattern and wide spread matters more.  For high beams, there's no such thing as too much, provided the light goes somewhere useful.  The only downside of really good high beams is that road signs are often too reflective and can be downright blinding. 

 

Another note on the low vs high beams thing: high beams aren't necessarily brighter than low beams, and on many stock single bulb headlight setups, they're only slightly brighter at best.  The biggest difference between what makes a low vs high beam is the beam pattern (and that's why there's a limit to how much light is useful for a low beam, as it only has a certain area to fill, so more light doesn't help you see further). 

RX8driver
RX8driver Reader
2/26/23 10:09 a.m.

I have a bit of experience upgrading headlights. I had a 2005 Focus where I opened the stock housings by placing them in the oven and prying the lens off, then installed some Morimoto mini H1 bi-xenon projectors into the factory housings (they attach through the stock bulb hole), then re-installed everything. In order to keep the DRL's I installed LED flashback turn bulbs and wired them so that they would light up white for DRL and amber for turn signals with a resistor in line to avoid the hyper flash. This was a definite step change compared to OE and no amount of lens polishing and relays would have done that.

On my current 2015 WRX, it came with halogen projectors and I installed a Morimoto HID kit using the factory housings. It too was a step change again and since they were already projector housings, the light pattern is pretty decent. I was having some issues after a number of years with modules dying and got fed up, removed them and put some LED bulbs in place. They were TERRIBLE. Light pattern was bad, light output was bad to the point that I kept checking the headlight switch to make sure the lights were actually on. The snow did not melt off the lenses either making it worse. After a couple days I ordered a new Morimoto kit and am back to being happy with the light output. To me the output is worth the long term reliability issues I ran into.

I would NOT recommend LED replacement bulbs and I would not recommend any non-halogen bulbs in a non projector housing. That is largely what you'll be seeing with oncoming cars blinding you, since they can't match the halogen beam pattern. In my commute in the winter, it's at dusk and there's plenty of traffic, so I can almost never use my high beams, so good low beams were my priority.

Datsun310Guy
Datsun310Guy MegaDork
2/26/23 10:20 a.m.

In reply to ddavidv :

I have a set of Hella's waiting for the right car.  I bought 3 sets on clearance at Wally World and I had a guy drive 75 miles in an old Land Rover to buy 2 sets off my Craigslist ad. 
 

OHSCrifle
OHSCrifle UltraDork
2/26/23 10:46 a.m.

Thanks for the responses. Thirty years ago I had some car stereo install experience... it's been a while. I'd rather not berkeley this up. Has anyone seen a kit with instructions for the wiring portion?

 

Edit: something like this but generic

dj06482 (Forum Supporter)
dj06482 (Forum Supporter) UltraDork
2/26/23 10:55 a.m.

On our '06 Rav4, the original housings were cloudy. I used the Sylvania kit (which worked great), and I upgraded the low beams bulb to the HIR style by trimming one of the tabs a bit (as mentioned by a previous poster).  Between the two changes, light output is much better. The high beams are solid now, but I'm also considering the HIR conversion there, as well.  We do a lot of driving on dark, windy roads, so the extra light is really a necessity.

OHSCrifle
OHSCrifle UltraDork
2/26/23 10:58 a.m.
DrMikeCSI
DrMikeCSI Reader
2/26/23 11:15 a.m.

The problem with headlights is a lack of a performance standard. The Escort in the picture above looks like it has Hella European headlights. I had the on my Pinto back in the Stone Age and the had a very distinctive pattern. A bright line with light below it ahead of the car and an angled pattern to the right to help illuminate the edge of the road. I had these on my Pinto and Fiesta, but those were the last cars that had sealed beams that I have owned. 
 

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
2/26/23 11:38 a.m.

In reply to DrMikeCSI :

Yup.  I am not worried about hitting the road, I am worried about looking at the horizon.  Your peripheral vision is much more sensitive to light than your center vision, so having a bright area in your peripheral vision KILLS your center vision.

The best headlights I ever had were on my Golf. They did not light up the road at ALL, but they lit up things in the distance just fine.  I did not like them at first until I realized how much further down the road I could see.

The ones in my S60 are the worst.  They are single bulb HIDs.  They put an intense bright spot on the road, which kills your night vision.  And then the high beams just change the beam angle, so they end up not being bright enough.

 

The 42 year old sealed beams in my RX-7 are a happy medium.

gearheadE30
gearheadE30 Dork
2/26/23 12:26 p.m.

Projector retrofits have become my go to for this, and lately I've used the Hella LED low beam projectors in a few application where xenon doesn't fit. Not quite as good, but still much better than stock, and only around $125 apiece if I remember right. They are not bi-LED, lows only.

I don't know why my phone makes the cutoff look so crappy, it's plenty sharp in person. There is a little more scatter caused by the projectors sitting so deep in the housing, but it reflects upwards very aggressively so it's this kind of band that you only see if you're 10' from the front of the truck. I only noticed it driving through a tunnel at one point where I could see this narrow band of light above me.

 

In reply to Pete. (l33t FS) :

That's interesting, I never understood why sometimes I felt I could see better with the fogs turned off on my truck - the fogs pretty much serve as ditch lights since the low beams don't do much for anything other than straight ahead.

 

ProDarwin
ProDarwin MegaDork
2/26/23 12:37 p.m.

Someone explain projector retrofits to me.  Are these fairly universal?  Are they bolt-in? I only remember people doing DIY HID upgrades in the mid 2000s and they always seemed to be arts and crafts projects gone wrong, held together with glue, hopes, and dreams.  The aiming of them was questionable at best.

Terrible automotive lighting is a huge pet peeve of mine. Every situation is different and there is no one simple solution.

The Tahoe PPV I bought had horribly clouded lenses. Like so cloudy/weathered a piece of printer paper was more transparent. I used a headlight polishing kit but resorted to my orbital sander and sandpaper after I blew through all the kit's polishing pads. It's 95% better but eventually I'll end up replacing the head light assemblies. After I cleaned the lenses up, I adjusted the aiming. Both lights were pointed almost straight down. Using the garage door, some painters tape and some maths, I got the pointing almost spot on. It's actually nice to drive at night now.

The GF's Wrangler had the original housings from 2007. 8 years of harsh FL sun had completely deteriorated the lenses. I tried a couple of polishing kits but due to the shape of the lenses and the UV damage, I was not satisfied with the results. I ended up replacing the housings with KC H4 housings. They are much better than stock. I thought I could improve the lighting a bit more so I installed Hella high wattage H4 bulbs. The difference was minimal and the extra heat caused the housing reflectors to become cloudy and reduced the light output to where it was before with the stock housings. Welp, that didn't work. Next step is to replacing the housings with quality LED assemblies.

Basically the formula I follow is:

1. Repair/replace the housings

2. Fix/adjust the aiming

3. Upgrade the bulbs

LED replacement bulbs are usually terrible but I have found a few that work great in the application. It's extremely dependant on bulb shape/type/brand and housing shape. If the bulbs throw light all over the place, I return them. I don't want to be that dick that blinds everyone on the road. 

Caperix
Caperix Reader
2/26/23 4:08 p.m.
ProDarwin said:

Someone explain projector retrofits to me.  Are these fairly universal?  Are they bolt-in? I only remember people doing DIY HID upgrades in the mid 2000s and they always seemed to be arts and crafts projects gone wrong, held together with glue, hopes, and dreams.  The aiming of them was questionable at best.

Most will have a number of mounting options including a threaded shaft at the back to go through the bulb hole in the factory housing.   This tends to make alignment fairly easy.  I have used the morimoto mini h1's in a few applications.  They are easy to mount & have good light output.

 

rslifkin
rslifkin UberDork
2/26/23 4:32 p.m.
Pete. (l33t FS) said:

In reply to DrMikeCSI :

Yup.  I am not worried about hitting the road, I am worried about looking at the horizon.  Your peripheral vision is much more sensitive to light than your center vision, so having a bright area in your peripheral vision KILLS your center vision.

The best headlights I ever had were on my Golf. They did not light up the road at ALL, but they lit up things in the distance just fine.  I did not like them at first until I realized how much further down the road I could see.

The ones in my S60 are the worst.  They are single bulb HIDs.  They put an intense bright spot on the road, which kills your night vision.  And then the high beams just change the beam angle, so they end up not being bright enough.

 

The 42 year old sealed beams in my RX-7 are a happy medium.

The low vs high beam issue you're describing is the difference between a good bi-xenon projector and a crappy one.  A crappy one throws a big light splash right in front of you and not enough light far enough away, so pulling the cutoff shield back for high beams doesn't do enough.  A good projector throws less light up close and focuses more of the light right at the cutoff.  So for low beams the brightest output is right at the far end of your vision range, and there's more light aligned to be thrown further down the road when the cutoff shield is pulled back. 

Basically, there should be a hot spot in the beam pretty much split in half by the cutoff shield, then less light as you get above or below the hot spot and a fade off to the sides (ideally the hotspot should be more of an oval so the brightest area is wide enough). 

With good projectors (and especially with a supplemental high beam of some kind) you can get a pretty good combo.  ECE spec halogen low beams can be a little easier on the eyes though, as the low beam tends to be a little dimmer and the cutoff is defined, but not quite so razor sharp. 

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