My friend just put euro lights in his 1983 300SD. The lights are rated for 60W. He has 2 H4 80W bulbs. Will the wiring in the car tolerate the extra 20W of current?

Not a good idea for a couple of reasons. First, as you mentioned, the wiring may be marginal for that wattage and think of the mess, and possibility of fire, if you end up with melted switches and/or wiring insulation. Second, there is a heat factor of the assembly. New lens can become cracked and/or distorted easily with excessive heat. These are the reasons they put ratings on the light originally. With the cost of euro's, why throw that money away?

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Sam

84 300SD 350K+ miles ( Blue Belle )

thanks so much!

Good question and great response!

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'95 E300D 313k miles
http://www.ourfullhouse.com

Thats an extra 40W of current. 20 x 2

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-diesel is not just a fuel, its a way of life-
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You can push the limits slightly and from my limited experience safely with Osram Hypers -

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=140297345263

This seller's been very helpful with my bulb inquiries.

Sixto
87 300D

I have the 80/70 watt H4's in my W124 depos. My experience has been good. Although I've only had them for about 6 months. I checked the wiring that I could get at and found no warm wires. Didn't blow any fuses either.
The light output is really a big improvement over the 60/55 watt bulbs.

i've had 100/90 watts bulb on my MBs for a long time. no problem whatsoever.. though i did upgrade my wirings with thicker gauge wires, plus relays and replaced the bulb socket with ceramic ones...

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Mike

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1975 200 - Sold (no pix);
1978 200 - Sold - http://www.pbase.com/hboy/redbaron
1979 300TD - Sold
http://www.pbase.com/hboy/greenwagon
http://www.geocities.com/hboy726/300TD.html
1985 230E - now my daily driver...

Unknown to me, my car had 80W headlight lamps . . . for at least 7 years! When one died, that's how I discovered that it was over-wattage.

The wiring was inspected and there was absolutely no observable damage to any feed wire.

From an engineering standpoint: 65W bulb runs 4.7 amps; an 80W bulb runs 5.8 amps.

Here's the current handling of popular wire sizes:

AWG --- Ohms/100ft --- Max Amps for Chassis Wiring
#12 ------- 1.588 ------------ 41
#14 ------- 2.525 ------------ 32
#16 ------- 4.016 ------------ 22

So you're not in trouble w/ an 80Watt lamp.

Personally, I replaced mine w/ Silver Star Ultra lamps and they produce bright, white light at 65 watts.

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Regards . . . . JimF
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'94 S500 Cpe

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