The other day i was looking around and i stumbled accross something. I did it and it worked and i'm not even using high wattage bulbs. Check it out http://www.ford-trucks.com/article/i...r_Brights.html

Took me about 30 mins to do this...

 

What we have here is nothing more than a heavy duty harness. You can skip the construction and buy one for about fifty bucks. In and by itself, it will not make for brighter headlights. If you happen to add higher wattage bulbs, it will because the stock harness does not have the higher current carrying capacity needed. It will also prevent frying your stock harness for the exact same reason. Unless you have higher wattage bulbs though, it's a waste of money, and constructed incorrectly, could cause all sorts of problems.

 

Higher wattage bulbs... like how high? I think i've got 65W in my fogs right now, the Silverstar 9005's. I've also got the Silverstar headlights.

- NCSU

 

Headlight Thermal Breaker?? I don't see that anywhere on my schematics....

Any procedure that states, "Don't attempt this without the beer" is automatically suspect.

The procedure doesn't address grounding, doesn't address the extra heat generated by the higher wattage bulbs, and all it manages to do is further complicate a relatively simple system by adding an additional pair of relays and fuses. Complete waste of time to gain a few more lumens from the stock lights IMHO, and illegal to install any brighter than stock lights.

-Joe

 

I could see where a New harness ( HD or not ) installed in a 1997 truck, if abused with higher wattage bulbs over it's life, could return them to stock brightness. Or maybe it was just the new socket being installed ( corrosion / dirty, worn out connector pins ) that returned it to stock brightness.

I have seen claims from HD harness manufactures, for a 47% increase in factory bulb applications with HD harness. Thing being, there is no data on the test subject used ( age, what kind of abuse it had seen, condition, etc ).

It is funny to see the number that get posted :
Factory harness :
P=12.68*4.5
P=57.06
HD harness with factory bulbs.
P=14.28*4.5
P=64.26

Someone see a problem with this ???? The bulbs are running brighter then spec'd ( 55W low / 60W high ). That is a factory bulb ?

Same with the Silverstar application ( same test subject..unknown ) :
Factory harness w/ Silverstar bulbs
P=12.69*5
P=63.45
HD Harness w/ Silverstar bulbs
P=14.3*5
P=71.5

See another problem ? The Silverstar is already running brighter then designed by the numbers returned, on the factory harness, if they got the reading correct.

For the case of running way over wattage, yes a HD harness is a must, and as Joe posted, you are running into heat issues.
This could manifest itself as shorter bulb life on the best case side, or worse case, damaged housings. This is a could list, not a; it will list.
Lots of factors come into the equation, such as usage. If the lamps see very little sitting still ( i.e used in driving applications so there is a good airflow ) either of the noted item might not happen.

The Ford Harness is not that bad. I have yet to get time to install the HD H13 harness with the Silverstar bulbs, to see if the factory harness is really an issue. Once I get a few min to install the modified harness, I will post the data. I got the dfuser.com harness, and did a test fit, modifying the ground lead length on one side, removing the fuseable link, in place of HD ATC fuse sockets, and increasing the power lead to the fuses for mounting considerations.

The fog lamp with 9145ST bulbs, I started in with a 12 AWG harness, but after looking at the power numbers on the factory harness, did not see a need for it. Again this is with the 42W 9145ST bulbs, not the high beam replacement ( which should be a 60W I think ). The 60W install, might be a case for a 12 / 14 AWG harness installation.

I will say my ZG-1000-A17 needed a larger harness installed, with the EU spec'd Silverstar bulbs. They were brighter then the US Silverstar bulbs, and the Kawi harness is a bit undersized to begin with, even in factory bulb terms. That is an application specific requirement for a HD harness.

 

Indeed... I don't understand where they're getting their voltage numbers... and how they're measuring the current as well. It seems a little hard to believe that the current flow is the same with both harnesses... I don't think the current consumed is a constant... I suspect that all three (wattage, amperage, and voltage) vary from one harness to the other. I would be surprised if the current was the same.

 

how about this??? cleaning your lenses. kits at autozone for 10 bucks just for that ,especially if you have a 10 year old truck. guranteed better brighness. why mess with wiring??

 

I run 20% brigher bulbs in two vehichles and is enough of a change for me without causing a need for wire changes.
On the truck, no other changes; on my car, I installed seperate relays for hi and low beams with seperate fused battery feeds for reliability, a number of years ago.
Reason for the relays is because the car has all the current running thru the headlite switch. Not a good thing.
I did make brightness test under the same conditions each time using a photograhic hand held light meter. The results was about 1/2 f stop increase at the same measuring distance in a dark garage.

The problems come in when one tries to run lamps with really hi wattage rating without upgrading the feed circuits. Like anything else there are limits.
You would not run three clothes irons from the same thin extension cord or the same wall outlet at the same time, for the same reasons.

The voltages measurements have to be made at the lamp sockets as the current is the same at any point in the circuit.
The power at the lamp socket is volts times current. The power at the feed point is the figured the same way but the 'difference' between them is the losses over the length of the wiring.
This is the place that causes all the problems and discussion beside the ability of the lamp sockets to pass extra current without overheating.

 

Well, i have some xenon 55w/65w bulbs that i bought at wal mart on sale for 16 bucks in my truck which should be brighter than stock. I rewired everything and i saw a diff. I took pictures with a camera, left it on a tripod to get from the same spot so the reflection would not be any diff. First picture i took, before install, i could see the housing and part of my grill. Second picture i took, after install, you couldn't see the housing and barely see the grill bc of the brightness diff. The post does make sense, bc of the long run you have to go from the battery, to the switch, then to the lights, not to mention on a small gauge wire.

 

GIJoe & SSCULLY,

I've got to agree with you on the math. Could this be the "new math" that never really took off? Sounds an awful lot like the math used to advertise / justify Turbulators, Fuel Line Magnets and Tornados. I'm not ruling out the possibility that doing this mod might make stock headlights brighter though, but I would challenge the real source of that improvement. Just taking apart connections that have never been moved / cleaned for many years and then putting them back together might be enough to remove some oxidation / resistance - which would make the lights brighter.

As for the HD harness, I ran one for a number of years with a set of 80 / 100 watt 9007 bulbs in my last truck. I doubt the factory harness could have handled that load and I wouldn't want to trust one I made myself. I got tired of pissing people off with that much light on low beams though.

 

Disclaimer... I mis-spoke about the current flow being different in my previous post. Upon further contamplation, yes, the current flow will be close, but not exactly the same as the resistance of the bulb (the current limiter) changes with temperature. Higher temperatures due to the increased voltage input and wattage output equal less resistance, so there will be some variation there.

Agreed, but we're talking about two different circuits, not two different points within the same circuit. The key is that the sum total of the secondary circuit's resistances through the connectors, relays, and wiring should be less than the OEM wiring's resistance. I'd love to see some direct measurements of the resistances, not some theoretical voltage numbers... If you look at it as a summation of resistors in series, you have a very simple DC circuit: A battery, a resistor, and a bulb. *If* the current flow through the bulb was unchanged, then I'd say, yes, the current would be the same. However, as I stated above, I don't believe that would be the case.

I'm still waiting to find the info on resistances of wiring per unit length... IIRC, 14 gauge wire is good for 15A, 12 is good for 20A, and there's no appreciable voltage drop until you start getting to lengths of 100 feet, but that's also with 110V AC... at 12VDC, you may start seeing some appreciable voltage drops at much shorter distances.

Where's Thermo when you need him???

-Joe