100 Holagen Bulbs

[BenzMeister]

Think it is safe to use 100 W holagen bulbs in my C289 vintage 1999? For both high and low beam. The wiring for the headlights looks awful flimsey to me. Thanks!!

[nokia8860]

The best way to run high wattage bulbs is to use a relay that is connected straight to the battery that way you will only be drawing very little current from your stock wires.

Using say a bosch spdt you would put the positive terminal of your stock low beam lights to pin 85. 86 would go to chassis ground pin 30 you would fuse for say 20amps direct to the battery and pin 87 would go to the positive end of you new 100w bulbs.

Basically what is happening is instead of drawing all the power to fule your 100W bulbs from the stock wires... which would eventually melt etc... you are only using the stock wire to "trigger" on the relay which will then draw current direct to the battery for you lights.

Make sure you use proper gauge wires for this as you dont want to cause and electrical fire. Hooking up a light relay like this is basically the same way you would wire up some foglights... same concept They best overkill way to do this is to have a relay for each higher wattage bulb you are gonna run so you need a total of 4 relays. :bunny:

[BenzMeister]

Yes, as you said it's about the same as aux., fogs thanks for the information.

[Deepchord]

1999 is vintage? What's a C289?

Did I miss something?

[BenzMeister]

Fine wine, vintage years :bunny:

[ryhi]

i got a set of mtec headlight (h7) but they are 100 watts < 150 watts...or sumthin like that...what would happen if i just plugged them in without doing any wiring mods? i want to run these bulbs as safe as possible, but can someone explain how i can actually go about doing this with easier terms? im not too familiar with this

[nokia8860]

Originally posted by ryhi
i got a set of mtec headlight (h7) but they are 100 watts < 150 watts...or sumthin like that...what would happen if i just plugged them in without doing any wiring mods? i want to run these bulbs as safe as possible, but can someone explain how i can actually go about doing this with easier terms? im not too familiar with this

You could plug it in but you may run the risk of melting the plug ends/wires as you are drawing more current through the thin wires.

The safest and soundest way is to run the relays. Purchase a relay (about 5-7 bucks) and follow the post I posted above and you will see what I mean when I say pin this to pin that. Its really easy to do.

However, if this is the first time doing electrical wiring you may want to consult your local shop with some help. A good source would be an audio shop that also installs fog lights as they would know how to wire up relays.

[ryhi]

what about the special "high wattage bulb harness" they sell at pepboys?

[BenzMeister]

I've been running with a set of H7 100 watts for my low beams for a month now, so far no melted wires or blown fuses. I tried a pair of H1 100 watts for the high beams, each time I turned them on of flash them, it blew a fuse.
Declaimer: this is my experience with my 99 C280, can't guarantee same results with any other car.

[nokia8860]

Originally posted by ryhi
what about the special "high wattage bulb harness" they sell at pepboys?

i havent seen this but if this is like the other stuff other shops sells then its what i have posted. relay and wires in which they mark it up way more than the sum of the parts because they sell a "kit".

[ryhi]

but in ur post it says to replace the wires with the proper gagues?...so i have to get a set of relays for each headlight AND replace the wireS?

[Scotty-C190E]

I think the mtec is the same low watt bulbs with a 100W feeling.

[nokia8860]

Originally posted by ryhi
but in ur post it says to replace the wires with the proper gagues?...so i have to get a set of relays for each headlight AND replace the wireS?

Rule of thumb. Each filament should have its own relay. So if you are just replacing your low beam for both headlights that would require 2 relays. Using this rule if you are also upgrading your high beams on both side as well you would need 4 total. Even if you are not running higher wattage bulbs you should consider adding relays as it will insure you are getting max juice from your battery.

As far as wires, you are connecting from the relay to everything else. Meaning use the proper gauge, dont get cheap and use extra speakerwire or single strand solid wire.

Also any spdt relay (30A rating would be good) will do. I only mention bosch because that is what I use.