High beam and fog lamp upgrade bulbs
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High beam and fog lamp upgrade bulbs
I had been looking into some options for improving the light output of the H7 high beam bulbs and the HB4 (9006) bulbs used in the fog lamps. My research led me to purchasing the Euro Osram H7 bulbs and the Toshiba HIR 9012 bulbs to use in the fog lamps.
In order to measure actual gains in light output, I relied on a Hoppy Vision 1 Image Processing Headlight Aimer, which provides a very close approximation of actual candela produced. Candela is the base unit of luminous intensity in the International System of Units that is equal to the luminous intensity in a given direction of a source which emits monochromatic radiation of frequency 540 × 1012 hertz and has a radiant intensity in that direction of watt per unit solid angle - in a nutshell, how much light output there is.
So first, I took base light output measurements of the stock high beams and stock fog lamps. The high beams produced 23,000 candela of light:
The low beams produced 2000 candela of light with the standard HB4 bulb:
The replacement H7 bulbs, the Osram Silverstars, are a better version of the Sylvania Silverstars offered for the USA market. I found a set on eBay. They came in this packaging:
Here's a comparison picture of the stock H7 bulb (dark tip), and the Osram H7 (silver tip):
The HIR bulbs were also sourced on eBay and are a 55w bulb, so the current draw is virtually identical to the stock HB4 bulb. The HIR bulb requires a small adjustment to the shape of one of the mounting tabs, and I used a Dremel tool for that purpose. After adjusting the tab, the bulb mounted into the fog lamp perfectly. Here's a photo comparing the bulbs:
The results were even better than I hoped for. The high beam output jumped up to 36,000 candela (from 23,000), a 56.5% increase in light output:
And the fog light output increased to 5,000 candela (from 2,000), a gain in light output of 250%.
Since both of the higher performing replacement bulbs are rated at wattages comparable to the stock wattages, I hope not to run into difficulties I've experienced in the past using higher wattage bulbs which required fuse upgrades and heavier gauge wiring harnesses. Now, I seek the darkness because I can light it up
In order to measure actual gains in light output, I relied on a Hoppy Vision 1 Image Processing Headlight Aimer, which provides a very close approximation of actual candela produced. Candela is the base unit of luminous intensity in the International System of Units that is equal to the luminous intensity in a given direction of a source which emits monochromatic radiation of frequency 540 × 1012 hertz and has a radiant intensity in that direction of watt per unit solid angle - in a nutshell, how much light output there is.
So first, I took base light output measurements of the stock high beams and stock fog lamps. The high beams produced 23,000 candela of light:
The low beams produced 2000 candela of light with the standard HB4 bulb:
The replacement H7 bulbs, the Osram Silverstars, are a better version of the Sylvania Silverstars offered for the USA market. I found a set on eBay. They came in this packaging:
Here's a comparison picture of the stock H7 bulb (dark tip), and the Osram H7 (silver tip):
The HIR bulbs were also sourced on eBay and are a 55w bulb, so the current draw is virtually identical to the stock HB4 bulb. The HIR bulb requires a small adjustment to the shape of one of the mounting tabs, and I used a Dremel tool for that purpose. After adjusting the tab, the bulb mounted into the fog lamp perfectly. Here's a photo comparing the bulbs:
The results were even better than I hoped for. The high beam output jumped up to 36,000 candela (from 23,000), a 56.5% increase in light output:
And the fog light output increased to 5,000 candela (from 2,000), a gain in light output of 250%.
Since both of the higher performing replacement bulbs are rated at wattages comparable to the stock wattages, I hope not to run into difficulties I've experienced in the past using higher wattage bulbs which required fuse upgrades and heavier gauge wiring harnesses. Now, I seek the darkness because I can light it up
Last edited by komp55; Dec 25, 2007 at 07:55 PM.
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From: ann arbor
2014 GL 350 on order
kompressed55: one of the best scientific treatments of this whole 'lite thing' Ive read. As a sequel to your lab work do the HID fog setup from James at Creative Autoworks for candela output. They cost 150 for the set and are 5000K in color-mine work great! Joker
