H4 bulb wattage dilemma
 

I have a 1982 300sd. Stock wiring and relays. I just got my Bosch H4 euros. The good folks at Capitol West Co. in Sacramento, CA. sent me a pair of high wattage bulbs I ordered. 100/90w H4 P43T Xenon Halogene in the Heliolite brand. Wiletta who owns the place said that she uses these in her 78 Mercedes and a 1991 model with no problems and has done so for five years.

Daniel Stern lighting emailed me and said, "You must stick with stock wattage to use your existing wiring. There is a persistent (and incorrect) rumor that Mercedes are so well built that you can safely and effectively run high-wattage headlamp bulbs without damage. Do so at your own great risk.

Use ultra high efficacy H4 bulbs, $17/ea, and H3 Gold bulbs, $13/ea."

Any of you have a definitive answer for me before I damage something?

Maybe Wiletta is one of those drivers I finger at night as they pass by on I-5 as I drive thru Sackatomato , I am tired of oncoming cars with blue or green or some kinda colored bright halogens, blinding oncoming drivers.

Be aware that besides excessive voltage drop in the wiring, you are likely to melt the socket and or bulb housing depending on what vehicle its going in. Putting hi wattage bulbs in later MB's (124, 201 etc) is prone to causing damaging to the headlite assy.
Case in point. A local shop replaced a melted headlight assy after they found the car's owner, a woman, had installed 100 W bulbs in it. A few months later same dame came in *****ing about one of her lights went out again, saying they must not have done a very good job, it cost a lot of $$ for those new headlites, blah blah blah :(
Inspection showed that someone had stuck in another 100W bulb. I believe they told her in no uncertain terms, no warranties for her lights and don't bring it back for this again!

The problem with the 300SD is the headlights are no good from the get go. Find some Euro headlites and use a Hella +30 55 Watt bulbs and you will be in great shape!

Electricity works according to pretty simple rules.

You need to first determine if your circuitry can handle the current demand of the lighting you are using.

Watts/Voltage = Current draw

So 100/12 = 8.33A per high beam. If both headlamps are on the same cicuit then double that, if high beams and headlights are on at the same time, quadruple it. Then add a little for wiggle room.

I just checked the wiring diagrams for my car, and they show a circuit for each high and low beam, at 8A each - which is not sufficient for the lamps you have. Don't substitute a higher rated fuse unless you also replace all the wiring attached to it.

Next comes heat. Most of the energy going into an incandescent lamp becomes heat, relatively little becomes light.

Basically I wouldn't do it.

Kevin

I'm a bit confused by the statement "stock wiring and relays" statement in the original post......

If the wiring is stock you don't have any relays involved, if on the other hand you have added relays then it seems to me you don't have a stock set-up anymore.

Euro lights have no problem handling high-power bulbs, I've been running 100/80 watt bulbs (with upgraded wiring and relays) for years - they work great.

In spite of what others have said here there is no comparision between "high-output" 55w bulbs and a 100W high beam.

Reverend, I thought we had put this to rest. The definitive answer is as follows:

If you have to run higher wattage bulbs then you must install proper relays to run them.

There is an excellent article on HID lights and the proper use of them at http://www.intellexual.net/hid.html. They usually get all the blame for the blue/purple glaring lights, but when they are done correctly with the correct bulbs and housings, there is nothing wrong with using them.

Halogens don't usually give off the blue/purple light unless someone has tinted them or their lenses. However, 90W low beams are about as pleasant to oncoming drivers as just running with your high beams on. In fact, I think normal high beams are 60W - 80W.

modern halgoen high beams range from 55 to 65 watts.

http://www.danielsternlighting.com/tech/bulbs/bulb_types/bulb_types.html

I think this settles it
 

I think this settles this in my mind. I appreciate the opinions. I think I am going to return the bulbs and not take any chances. Thanks.

noooooooooooooooooo
 

check the diy pages here for a simple lighting change. it is complete with pix.

I had higher . . .
 

. . wattage bulbs in my MB and they have been there for 6 years (didn't know they were there!). The wiring was fine as well as the plastic connector that mates with the H4 bulb; no burning, etc.

I replaced them (w/ a legal version) and cleaned the inside of the glass. Details contained on my page, Menu#26.

They do make H-4 55/100 watt bulbs..........Low beams nobody gets blinded........and high beams you are going to blind them regarless of wattage.

I put one in My Harley shortly after I almost went through a barbed wire fence one night when I didn't see the road make a 90 degree right turn , I barely got stopped in time. THat would have been a ugly thing to do on a bike.
Been running one ever since 1983.

I'm inclined to think that the 55/100's would be acceptable using the existing wiring for the simple reason that the high beams are only on for a very limited time, and, therefore, the capability to build heat is simply not there.

But, if you were to run them for hours on end............................... :confused:

I would expect an 8A fuse, the standard for the high beam circuit, to blow with a 100W load.

Kevin

Something is not right here, Kevin.

The standard 60W high beams would use 10 amps for two bulbs, correct? :confused: