Hoppy

I've got a pair of PIAA Superwhite headlight bulbs. £50 a piece but very good, and I've sung their praises on here before.

Until now that is. One dipped beam blown. I've had them about six months but over summer they've had hardly any use. And now when I really need them one has gone pop. I remember from another thread that someone else had this happen. I don't think I've ever had a headlamp bulb blow before now.

I'm relunctant to fork out another £50 if it's just going to blow again. Are these PIAAs prone to blowing or have I just been unlucky?

Any advice appreciated.

Hoppy

DIGGY

I seem to recall seeing a few posts on these lamps blowing or any "uprated" type, it seems to occur more if the engine is turned over with the lights on, to get the extra brightness i believe the filament is made thinner and therefore will burn hotter (produce more light) this is only made possible by the use of more "exotic" (read expensive) gases in the glass "bubble" to prevent the filament from burning through, When the engine is turned over the voltage applied across the lamp is reduced, the result of this is for more current to flow through the filament (ohms law) hence overstressing it and therefore weakening it, over time this will lead to premature failure, must be bored at work one hell of an explanation!!!!!!!!!! or it could be that you've got a friday afternoon model!!!! i believe you can buy a device to stop the engine being turned over if the lights are on.....seems a little pointless to me but hey what the heck.............. I personally am on the look out for the gas discharge lamps and power modules in a breakers from a beemer or omega etc to see if they fit in. light output is fantastic and colour temp closer to that of daylight which our eyes operate more efficiently at or so i am led to believe.....no luck as off yet, perhaps they all crashed in daylight as they have all been front enders so far haa haa..

Hoppy

Diggy, thanks for your reply. Very helpful and makes sense to me.

I know a bit about photography and what you've described reminds me of the old 'photo-flood' bulbs I used to use for studio stuff (now overtaken by flash). You could run a very ordinary looking studio bulb at 1,000 watts but they got incedibly hot and only lasted 90 minutes!

While in 'photographic' mode I disagree that the colour temperature of daylight gives better low-light vision. The eye is most sensitive to yellow-green (the colour worn by road workers and traffic police) and blue-tinted lights actually reduce night vision slightly. They may 'look' whiter and therefore brighter, but they're not.

I think I'm going for the twin-headlight conversion. Pricey and probably a pain to fit, but hopefully a good and reliable solution.

Hoppy

Chris L

Hoppy

I use the Superwhites and I've also sang their praises on this site - they are very good. However, I've just had the dip beam filament go on one of the bulbs. I'm always very careful to not abuse them and when I looked at the bulb there was no sign of discolouration that would suggest overheating.

It appears that the filament simply broke. I spoke to PIAA about this and they were surprised that it had blown (only been in about 4 months (well they would be, wouldn't they )). However, they are replacing it FOC (despite being outside the warranty period).

If it happens again, then I would consider it more serious and would complain.

Chris

Hoppy

Yesterday, with one blown dipped beam, I drove home with the headlights on full beam but the leveller control on 4 (pointing down). It got me home and didn't seem to trouble on-coming drivers.

This morning I went to replace the broken bulb and also checked the other side. The dipped beam filament had completely evaporated!

So, two blown dipped beams on two PIAA Superwhites in two days. Not impressed. It's definitely the twin headlight kit for me now.

Hoppy

Huxley

I have a wiring diagram on my site to stop you starting your car with the lights on

I've had my PIAA lamps since the begining of the year and still going strong, the kit will cost about a fiver or so for the bits

Well worth the small outlay and it's easy to fit

mattski

chaps, is the difference the PIAA bulbs make really huge? I currently have 'upgraded' bulbs and of course would love some more light but part of me thinks it's better to put the money toward either the PIAA or Cibie driving lamps.

comments?

sunilp

Well, ultimately its better to have the lamps, but you can use the headlights all the time where you cant drive around with your full beam.........I am very happy with my PIAA BC2s, make a huge difference. I wont bother with the driving lamps as i dont live out in the sticks, cant drive fast (cue Danny Fisher), and dont do A Roads.

Sunil

AndyMc

Hi all

It would seem as though the Scoob is prone to blowing both bulbs at the same time.Both the 120w bulbs in my PIAA driving lights blew together after seven months use. I have never started the car with the lights on so I don't think that caused it.

TonyNesta

Wow - same thing happened to me. One BC2 blew 2 weeks ago, other one last night! Had them over 12 months though, and very happy with the output.

cwal1

Tony,

Are you going to Donington on Sunday - if so can we meet up ?

Chris Wainwright.

Dave T-S

It's quite simple - as soon as one bulb blows it puts more juice through the other one. Bulbs like running at a constant voltage/loading. They don't like surges/changes in load/voltage etc. More strain is put on the second bulb when the first one fails and it also fails shortly after.

Dave T-S

Sunlip
Danny - mind if I get in first? - in your circumstances (kerbcrawling 15 year old schoolgirls in Croydon) you don't WANT to go fast.

Yew wooden loike the sticks boy we baint got no schools ere.....

sunilp

Actually Dave, i find the 15yr olds can handle the speed, its the 11yr olds that have difficulty............

Dave T-S

Sunlip
Lowered the criteria again have you.....

TonyNesta

Got my replacement SuperWhite BC2 bulb today and get this - its purple tinted, even though the bulb ring states 'Clear white'!!!! Thought I'd been sent the wrong one, so got straight on to GGR who, after checking with PIAA, confirmed it is the correct bulb, and that the purple tint will disappear once I start using the bulb. To their credit, GGR advised they will replace the bulb if I'm not happy. I'll let you know how I get on.

Hoppy

The blue/purple tint on the bulb is the really daft bit. It reduces the light output substantially by filtering out the part of the spectrum to which the eye is most sensitive, ie yellow/green. Metal filament bulbs naturally produce light with a yellow emphasis, and yellow light equals more light in this case. It might not 'look brighter' but you can see better.

The blue tint is pure fashion.

Hoppy

TonyNesta

Tried it out tonight - no blue/purple tint at all in the light.
I must watch too much X-Files....

sunilp

more like too much masturbation

Dave T-S

.....there speaks an expert.....

sunilp

affirmed by a "smaller" expert Dave?

[This message has been edited by sunilp (edited 10 November 2000).]

MTR

Hoppy,
Try having a look at this site for tech info on bulbs.
It is from a thread 12 months ago.

Chris L

MTR - welcome back

I read this site a few weeks back - interesting stuff and not entirely surprising. But I think most would agree that the standard bulbs on the Scoob are a pretty poor affair - anything must be an improvement!!

Chris

MTR

Chris L,
Thanks for the welcome.

Just as conversation, I used to own an AVO Mk1 Escort Mexico, that had as standard, a relay that powered the dipped beam filament of the headlights when full beam was switched on, therby increasing the total wattage to 230 Watts (55+60 x 2)in lieu of 120 Watts on full beam,reverting back to 110 Watts on dipped beam (2 off at 55 Watts H4 bulbs, not standard bulbs, as I had Cibies fitted).
Suprisingly even though the total wattge was higher it didn't feel nice to drive fast at night, as I felt the foreground lighting was too prominent, and appeared to make the distance illumination semm dim, in comparison, and it lessened my confidence level regarding were the road went.
With additional longe range spots fitted, everything seemed better, and I could drive faster.(road rallying)

As an aside, there was one instance, I think on the RAC, were Roger Clark started a stage as the light was beginning to fade, and chose, in contrast to all the other competitors, not to fit any spots to the car, to save weight, and also drove without any lights on at all.
His theory being was that his eyes were used to the prevailing light level, and he could judge speed and distance better with the low level of natural light, than with man made ilumination.
He won the Stage.

It just confirms a little of what has been said about people believing they can see better with a certain colour/type of bulb, when the physics of light may say otherwise.

Its all a matter of how much confidence you feel at night,with whatever set up you choose.

My friend used to compete in road rallies with Lucas sealed beam units (eek), because he had never been used to Halogen lights, and thought they were unecessary.
I didn't agree with that point, however it didn't slow HIM down.(And he wasn't a bat, but was a bit batty)

Cheers MTR

Hoppy

MTR, thanks for that link. Guess I was right about the colour, then! I've not read the whole site (he can waffle on, can't he) but I couldn't find a reference as to why my PIAA Superwhites blew so quickly.

I popped into Halfords today and they have three types of bulb. Their 'regular' bulbs appear to have the dichroic coating which he disapproves of, the 30% brighter* ones are clear, and on the pack of their blue-tinted jobbies (which endow your car a "high-tech" look!) they warn about early failure - not recommended for high mileage drivers, whatever the that is supposed to mean.

Hoppy

PS *30% brighter sounds a lot but it's actually bu99er all. You'd need a side by side comparison to notice it.

Chris L

MTR

Nail hit firmly on head I think - confidence. If people can fit these bulbs and it increase confidence (without inducing acts of lunatic driving in the dead of night because of over confidence) then I think that is a good thing. I much prefer the light from the PIAAs - imagined or not

Hoppy I have a couple of the Halford's bulbs as my 'spare set' - they are pretty good (and at £10 each - good value).

Chris

john catania

The PIAA bulbs sound like a good idea! I have the PIAA Driving light conversion which is excellent, but the standard lights are in need of some help. What is the wattage and does anything need an upgrade?

Chris L

John

PIAA do two types of Superwhite bulb - standard 12V H4 replacement headlights. These are rated at 60/55W and 'E' marked and road legal. The other type are called BC2 and are rated at 80/80W - these are not road legal - fit them at your discretion.

Full details at

Dave T-S

MTR
Been there with the Mk 1 Mexicos - great fun cars in their time - and you can still buy the HILO dipping twin filament Oscars from Demon Tweeks today!!!

Sunlip
I totally agree with your comment that I am smaller than you. And not only are you much fatter than me but much uglier too!!

sunilp

Somehow i dont think so Mr Middle aged spread