[Fwd: Found a cure for crappy low beams...] long

[T Berk <tberk@mindspring.com>]

This post is forwarded from the Subaru newsgroup (GF has a WRX Wagoon)
and is intended to refer to relay vs non relay thread that was on the
list recently. It is pretty non brand specific in terms of one auto
manufacturer or another and in the interest of On Topic-ness I humbly
submit the following for your approval.

TBerk
btw Daniel Stern's link is <http://lighting.mbz.org>

Daniel Stern Lighting wrote:
> 
> On 2 Dec 2001, Rockhead wrote:
> 
> > When you go from a 55-watt factory bulb to a 100-watt aftermarket
> > bulb, you are increasing the heat output by nearly 100%.  The extra
> > heat of a hig output bulb will quickly cook the reflector of the lamp
> > housing as well as the bulb.
> 
> ASSUMING high-quality bulbs (Osram, Philips, Narva, Norma) and not
> third-world garbage (PIAA, Heliolite, Phoenix, Polarg, Eurolite, etc), the
> bulbs can handle it.  Whether the materials of the headlamp itself can
> take it is on a case-by-case basis.  There is a wide range of materials
> used in the construction of headlamps.  Some of them are at the
> bleeding-edge limit of their thermal resistance with stock-wattage bulbs,
> while some of them have no problem handling massive thermal overloads.
> The important point to remember as regards the lamps themselves is that
> one is always taking a risk of headlamp destruction by overheat damage.
> That damage may take the form of melted, distorted, dulled or cracked
> reflectors, heat-cracked lenses, deformed bulb shields, deformed or melted
> bulb holder parts, or, in extreme cases, heat welding of the bulb into the
> headlamp (this makes a VERY expensive "sealed beam"!).  With poor-quality
> bulbs, one also runs the very real risk of grenade damage, when the
> massively-overpressurized, poorly-made bulb explodes inside the lamp
> housing.  The destruction is almost always total; hot, sharp shrapnel at
> extremely high velocity and close range doesn't leave much behind.
> 
> Then there is the issue of the wiring, which despite the occasional "Gee,
> I've been running 130 watt bulbs on my stock wiring with no problem"
> story, is NOT up to the task of any kind of overload.  Stock headlamp
> wiring is usually marginally-to-moderately undersized for even
> stock-wattage bulbs, when brand new.  The wiring that improves with age
> has, so far, eluded scientists.  Bulbs that present a 50 or 100 or 150
> percent overload on stock wiring are an utterly foolhardy risk to take;
> the chance is quite high of a serious electrical fire.
> 
> Even if one does not burn the car down with overwattage bulbs, remember
> that *tiny* changes in voltage to the bulb give *large* changes in light
> output.  The relationship is not linear; a 5 percent voltage drop robs 15%
> of the light output, for instance.  With voltage drops with
> couple-year-old stock wiring and stock bulbs running between 2 and 8
> percent, and remembering that increased current pull through the same
> wires will massively increase voltage drop, you will be shooting yourself
> in the foot from a lighting performance perspective unless you install
> wiring adequate to the task at hand.  Note that often, simply upgrading
> the wiring and (installing) relays and staying with stock bulbs gives a
> *very* substantial improvement in lighting performance.
> 
> > In addition to replacing the bulbs more often
> 
> True.  High-wattage bulbs have a shorter life than low-wattage bulbs of
> the same design.
> 
> > you will find that the bulb socket will eventually melt as
> > well.  If you're lucky, you will only have to replace the socket, not
> > the harness.
> 
> See above.
> 
> > The heavier filaments used in high output bulbs take a fraction of a
> > second longer to heat up when energized.
> 
> MMmmm...no.  A couple of nanoseconds.
> 
> > This is noticable when
> > turning on high-output high beams.  You may have a split-second of
> > total darkness before the bulb heats up.
> 
> Only if you aren't feeding the bulbs properly with heavy wiring and
> relays!
> 
> > Modern relays and switches are usually capable of handling the
> > additional power load.
> 
> Usually NOT capable of handling the additional power load.  If you've ever
> dissected a typical factory-equipment lighting circuit, you know that it
> involves LONG lengths of THIN wire and TINY contacts.
> 
> > Do youself a favor and invest in a quality set of driving lights.
> 
> Driving lamps are only for use with high beams, only when there are no
> other vehicles visible in front of you in either direction.  They must
> never be used in traffic.  Therefore, they are of rather limited use to
> most drivers who rely on their low beam headlamps most of the time.
> 
> --Daniel
> 
> TO WRITE TO ME:  Remove the headlamp from my return address.
> 
>                      .______DANIEL STERN LIGHTING______.
>                      |     http://lighting.mbz.org     |
> ---
> dastern "at" vrx "dot" net
> Automotive Lighting and Signalling Services
> NBCS b6f+wg++rp

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