Night Flaming

[quk@sievers.com (Phil Payne)]

In message <961202125922_1587622147@emout06.mail.aol.com PDQSHIP@aol.com writes:

> Just about every prorally driver runs no more than 100w on the HI
> beam for a bunch of reasons, the biggest being reflectance of
> light back at the driver....

I'm told by the expert preparers of such cars here that they run
130/100 or 130/80 mains.

> A euro low beam with a 55w bulb is what you are supposed to use,
> above that, you might as well get yourself a driving light, it
> will be more effective...

It's a compromise, one of the components being that the "average"
user might well drive around with mis-adjusted lights and another
being bulb life.  Can you imagine "Joe Public" complaining that his
"fine German automobile" blows a headlight bulb every six weeks?

> The H4 euro and z-beam pattern are designed to be effective as a
> low beam and a fog in the same lens, something well accomplished
> with 55w bulbs (as comes stock with EVERY true halogen fog lite
> h1/h2/h3)...

True.

> What happens when you add lumins to the low beam is that the lite
> is brighter, but so is the reflectance of humidity, kinda like
> running a hibeam in a snow storm, tho now humidity does the same
> thing....   On a clear nite with low humidity a 100w+ low beam
> euro lite will be effective, but the cost will be the first time
> you drive with those lites on in the fog, or even a humid nite,
> you have decreased driver visibility, dangerously so, esp if you
> have no fog lites, or can't shut the lows off with fogs on....

I have seen no trace of this on a humid night, but it's certainly
debatable on a foggy one.  As UK law used to _require_ that lows
be switched off when fogs are on (and there's little point in fogs
otherwise) I _can_ switch off the lows in fog.  So far, my choice
when the fog has been that bad (as it was here about two weeks ago)
has been simply not to drive.

> As you increase wattage sign reflectance increases too, ...

Yup.  _Definitely_ an issue when approaching the so-called
"traffic calmed" villages in the UK, where oversized speed limit and
hazard signs have been erected.  The high beams are blinding, but
the lows are OK.

> so does the sensitivity to vibration...   A hi wattage bulb
> will reflect signs to the point where you are flash blinded here
> in the states, btdt, to say nothing of the guy coming at you who
> is blinded by your cool hiwatts....   Hi wattage also
> exponentially increases vibration effect, actually increasing eye
> fatigue, in a big way....

UK drivers are not slow to complain if they feel your lights are too
bright - they blind you right back.  I have them adjusted lower than
stock - as you comment, they're designed for fog use as well and the
top of beam cutoff is _very_ sharp.

> And audis aren't known for their non vibrating headlite assblies, I assure
> you...

There's a damn sight less vibration in the body-mounted headlight
assemblies than there is in any lights mounted on a beam.  I drove
for ten years in Germany - oncoming Porsches are characteristically
easy to spot from headlight vibration, but not Audis.

> Wattage has little effect on true visibility, the lens, the
> reflector, and proper aiming does....

The resolution of the human eye is directly proportional to the
illumination of the target.

> In fact, the Rallye 2000 comes stock with 55w h1 bulb, and has
> been the standard in the rallye field for almost 20 years now,
> 100w are put in them for the "dry" rallyes, but rarely, the gains
> are minimal compared to just getting the right lens (pencil
> beam)..

Yes, but rally cars typically carry six or eight lights, aimed to
give wide coverage.  On low, I have just two reflectors using the
wide, flat-topped Euro beam pattern.  Pencil beams would be useless.

> Some research on what is happeining in the ProRally world should
> translate to our street world, the object is to get the best
> light available for all conditions, without having to hang 8
> lites on the bumper...

Resilience is a big argument in rallying.  One failed bulb can
take out half my light - but I can afford the time to stop and
fix it.  A rally driver can't - 8 x 55 is _much_ better for him
than 2 x 100.  He can lose three bulbs without having to stop.

> PR are run at nite, in ANY and ALL weather, ck what they are
> running...

There's no one coming the other way on a rally ...

> If you wanted to maximize a euro lite, put 55w in the low, 65 in
> the outer high, and a 100w in the inner high with a switch for
> it....  That way, in dry conditions you have the advantage of the
> 100w bulb, but in more reflectance conditions you can shut down
> the inners and just run the H4 hibeam....

Well, you're entitled to your opinion.  I ran like that for two years
and would _NEVER_ go back to it.

> For the US folks, get the eurolites, or at least a good set of
> aux lows....   For the euro equipped, don't try to make the lites
> something that it wasn't designed for....

I'll concur with the first.  I'll point out that the usual setup
of Euro lights is a compromise.  I do _zero_ city driving and very
little motorway driving at night - my driving is almost exclusively
on relatively remote main roads out in the country.

> Properly aim them, put some thought into some aux liting (mine is
> all on a removable lite bar for city driving), talk to a Rallye
> driver before you go for lumins, that just isn't the object of
> the lite game...

I'll also concur with the aiming - I overhauled both my headlight
assemblies at the weekend, and just ordered new adjusters from
The Parts Department.  Some of the adjusters were siezed and the
screwdriver recesses were destroyed.  P/n 855 941 141A is the
Cibie adjuster screw and p/n 855 941 135 is the little clip for
the back.  I'll also comment on _cleaning_ them, which is something
I do before every trip.

> Gotta play?   Forget the bulbs....  Put amber in the fogs,

Amber?  Even monochromatic sources are now heavily discredited,
much less absorption filters.  This is the old canard about
"night driving glasses", which are now thankfully _banned_ in
the UK.  It's also illegal to drive with non-white headlights
here.

> ... spend some money and time designing in-cockpit lite control
> for "tuning" lite-on properties,

It's illegal to use driving lights without low beams here.  Some
configurations will get you pulled over instantly.  There are
also restrictions on what you switch with what, and requirements
for warning lamps visible to the driver, etc.

> .. get some aux lites that do what you are trying to do, bulb
> swapping might be fun, but does little in reality...

One of the major objectives is not to modify the exterior of the
car.  And _you_ might think it "does little in reality" but you
don't sit in the driving seat of my car on long cross-country
excursions.  Believe me, they make one _hell_ of a difference.

--
 Phil Payne

 (phil@sievers.com, despite what the bounces say.  If I don't
  reply, your message is probably still stuck on a Demon punt.)

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