Changed dipped beam to X-Treme 80s. Using VCDS (Vagcom) to make the changes actived 'Scandinavian Lights' then set headlight power to 32%. It acts like the dim dip system introduced in the early 90's. If fitted the fogs can also be illuminated with similar low power levels.

Light switch off, engine on: side lights come on plus 32% headlight output. Instrument/internal back lighting stay off.

But then surely if you change the element size then you will be dissipating the same energy over a smaller space so the element itself if hotter at a spot temperature.

Eg 50W bulb will drop 50W (It's a perfect system ok ) as light and heat over the element.

If you have a 10cm element then you're dropping 5W per CM combined as light/heat.

Make that element 5cm and you're then dropping 10W per CM combined as light and heat.

Say a bulb is 20% efficient, so the heat is 4W per CM dissipated on the 10cm bulb.

Make the shorter bulb 50% efficient so that gives twice the light output per cm, but then you are now hitting 5W per cm.

The greater amount of energy is coming off as heat per CM of that wire so a spot temperature would surely be higher for that bulb element.

The blackening is metal vapour depositing on the cooler glass, the blister will occur because the metal vapour will soften the glass envelope.

I think this thread has convinced me against +90% Nightstars. The +50% Silverstars saw me through two winters on my last car and at < £20 from autobulbsdirect I think I'll stick with that solution.

All that said, the bog standard Osrams I took out of the Vectra when I got it (6 mo/16k old) were quite well burnt. The glass was white at the top above the filament.

I've HIDs in at the moment, but one of them is on the jitter, will probably stick in some NB's until I get the HIDs sorted...

I got H1 and H7 Silverstars in a BOGOF offer from Autobulbsdirect (Recommended). Noticeably better than OEM bulbs.

Only problem I had fitting was disconnecting the connector. I couldn't get this apart on either side and managed to pull the whole thing out on the O/S. You can still manage without disconnecting, it would have been easier with the unit on the bench.

where they genuine or counterfeit stuff ?

Just coming back to this thread, I put a pair of Halfords Extreme Brilliance +90% bulbs in when my HIDs failed. They're not great, I think the factory fit Silvanias were better...

Will probably go for a set of +50% bulbs when the Halfords jobs burn out, which probably won't be too long.

where they genuine or counterfeit stuff ?

My Silverstars looked genuine enough in proper packaging and look pretty much the same as the OEM ones fitted to SWMBO's previous Jazz.

Still puzzled about how the connector comes off though!

Aside from faults,

the nightbreakers i used to replace my main beams seem showing a marginal improvement on light. Surely not worth the hassle of fitting them. That's my mileage, anyway.

I too have experienced the dreaded 'blistering'... so I wrote to Osram.

And they have now written back, both blinding me with science and hinting that my Furby is a little generous with its volts:

Hello Mr Wobblytickle,

The significant improvement in light output of OSRAM NIIGHTBREAKER bulbs

is widely acknowledged and feedback from customers is almost unanimous

in praising the beam performance.

To achieve this improvement, the colour temperature is boosted and this

does inevitably result in a lower life compared with standard bulbs.

The life on all bulbs is very dependent on the applied voltage and even

a small increase above the designed value of 13.2V will result in

reduced life. As an example, a vehicle voltage of 13.9V will halve the

bulbs life. This can certainly affect the actual life achieved in the

vehicle.

As part of the ongoing development programme, work was carried out in

2008 that resulted in a significant increase in the life performance of

H7 and H4 NIGHTBREAKER bulbs without sacrificing the renowned beam

performance.

Best regards

Keith Raftery

Technical Sales Manager

Someone get out the multimeter...

I imagine that the 'work carried out in 2008' was in recognition of the very short life of the bulbs.

I must have got some 'old' ones, as mine lasted all of six months.

Would be interesting to know what they changed.

Edited 14 February, 200917 yr by Mr Wobblytickle

Would be interesting to know what they changed.

And whether the change/s decreased the light output or not.

And whether the change/s decreased the light output or not.

As Osram are still calling them "+90%", legally the output would have to be the same or greater.

I'm gonna email Keith asking whether the 'voltage buck pass' would also account for the 'black blisters' on the glass.

FYI. Mr Rafferty replaced one set of bulbs FOC and when they went the same way provided, at my request, +50% also FOC. I could not fault his customer service only the bulbs.

Great - all very interesting. What's the best one to go for in the dipped beam though? I want the best combination of improved light and longlife.

Just had my dad's Veccy dipped beams upgraded to Philips Xtreme.

Light does look better!