I installed a set of Depo headlights in the 80 a few weeks ago following Ebag333's review (which includes MOT's comparison to the factory Euro and JDM lamps) of them versus stock last year. His review is here:
https://forum.ih8mud.com/80-series-tech/530350-depo-headlights-vs-oem.html
One concern I had was that these are designed to replace the Eurospec lamps and people here in the U.S. that have been installing these lights have been running them with the H4 only for the low beam with the H1 driver's lamps flipped on the as the high beam. As the H4 is designed to run low and high beam, I had Susquana motorsports build a custom harness for me that properly switches the low and high beam as well switches on the driving lights portion with the high beam. The harness came out beautifully and I posted my comments about it here:
https://forum.ih8mud.com/80-series-tech/611546-depo-wiring-harness-install.html
Well, now that I have had the Depo's installed for a few weeks and been able to get them properly adjusted and spend some time with them, I wanted to post my review of them and provide beam shots with the H4 element wired correctly.
For reference my comparisons for stock are with the HIR 9012 and 9011 bulbs, Depos with the Osram H4 85/80 bulbs and H1 50+ bulbs in the driving lamps.
Low Beams:
A definitive improvement over the factory U.S. spec lamps. The low beam pattern is what is termed an ECE/U.S. hybrid with a sharp cutoff and kick up on the right side to help illuminate signs (the U.S. allows more stray upward light than Europe, but both countries have modified their regulations closer to each other over the last 10 years that most European cars come with lights now that satisfy both specs). Under the cutoff the beam is well distributed with no hot spots and good throw right out to the cutoff. I originally felt there was too much foreground illumination, but this was solved when I readjusted the horizontal spread to narrow it.
While the low beams work well, the one weakness they have is a lack of side illumination compared to a good HID projector. This is simply a result of light output and distribution. With an HID fixture they have more lumens to work with, so the extra light has to spill further to sides in order to not exceed ECE/US maximum output requirements (yes there are minimum and maximum outputs for all spots in the beam), which in turn helps light up the sides of the road. The limitation of the Depo's is simply a function of them being a halogen design. The Depos put out as much light and have as much throw in the main beam as an HID, they simply don't have as much width. In comparison to the stock lamps, they have more width, but the falloff to the sides is faster so more noticeable.
On a scale of 1 to 10, using my 2006 BMW 530i with Bixenon lights (which also swivel in corners!!!) as a 10, the Depos rate about an 8, and the stock lamps about a 5. While the stock lamps were great when they came out, it is amazing how much lighting has moved forward in the past 20 years.
For back road driving, I add to side illumination by turning on my Hella 1000 lamps with corning lenses. These are no longer made, but were designed for use by rally drivers to provide better side illumination. They are between a fog and driving lamp, having the limited vertical distribution of a fog lamp, but slightly less width and greater throw (about the same throw as a standard low beam). I have included in my pictures below photos with and without these lit up supplementing the low beams.
High Beams:
This is important. When the Depos are properly wired to switch the H4 element turning on the high beams changes the pattern. The high beams focus further down the road and provide a more diffuse side illumination that extends much further than the low beam. This is important because it decreases foreground light (which causes your pupils to dilate) and allows you to focus further down the road. When combined with the H1 driving lamps built in, they have incredible throw, actually a fair bit better than the stock lamps which are still good in this regard.
In comparison to a bixenon HID, the Depo's are different. On the plus side, the outthrow the HID's. On the other side, because of the driving lamp element, they do have a hot spot from their focused long throw. This will happen no matter what driving lamp you have, it is simply a product of getting a long throw.
Overall:
The depo's are a worthwhile upgrade. To do them properly with bulbs and a wiring harness the upgrade runs about $450. If you want more light, the Depos form a great base for performing an HID retrofit with bixenon projectors. The HID retrofit would provide better side illumination and combined with the standard driving element a wonderful high beam with lots of broad distribution and throw. I am not doing the HIDs because of cost. Good HID projectors, ballasts, bulbs etc., are $300-500 and if you don't want to mod the Depos yourself, you are looking at another $300-600 to have it done properly.
Now to the beamshots (please excuse the grain, my DSLR is having some issues so these were shot with a point and shoot, with the exception of the wall shots, all were shot at 1/8 second, F3.3 and 24mm equivalent lens):
The first two are the low and high beam on a wall. Please ignore the slight tilt down to the right, that is my driveway not the lamps. On the low beams, notice the clean cutoff (not projector razor sharp, but sharp) and the kickup on the right for sign illumination. Also note the uniform distribution under the cutoff with no hotspots. On the high beams note the smooth hotspot with smooth falloff and nice side illumination with no hotspots.
https://forum.ih8mud.com/80-series-tech/530350-depo-headlights-vs-oem.html
One concern I had was that these are designed to replace the Eurospec lamps and people here in the U.S. that have been installing these lights have been running them with the H4 only for the low beam with the H1 driver's lamps flipped on the as the high beam. As the H4 is designed to run low and high beam, I had Susquana motorsports build a custom harness for me that properly switches the low and high beam as well switches on the driving lights portion with the high beam. The harness came out beautifully and I posted my comments about it here:
https://forum.ih8mud.com/80-series-tech/611546-depo-wiring-harness-install.html
Well, now that I have had the Depo's installed for a few weeks and been able to get them properly adjusted and spend some time with them, I wanted to post my review of them and provide beam shots with the H4 element wired correctly.
For reference my comparisons for stock are with the HIR 9012 and 9011 bulbs, Depos with the Osram H4 85/80 bulbs and H1 50+ bulbs in the driving lamps.
Low Beams:
A definitive improvement over the factory U.S. spec lamps. The low beam pattern is what is termed an ECE/U.S. hybrid with a sharp cutoff and kick up on the right side to help illuminate signs (the U.S. allows more stray upward light than Europe, but both countries have modified their regulations closer to each other over the last 10 years that most European cars come with lights now that satisfy both specs). Under the cutoff the beam is well distributed with no hot spots and good throw right out to the cutoff. I originally felt there was too much foreground illumination, but this was solved when I readjusted the horizontal spread to narrow it.
While the low beams work well, the one weakness they have is a lack of side illumination compared to a good HID projector. This is simply a result of light output and distribution. With an HID fixture they have more lumens to work with, so the extra light has to spill further to sides in order to not exceed ECE/US maximum output requirements (yes there are minimum and maximum outputs for all spots in the beam), which in turn helps light up the sides of the road. The limitation of the Depo's is simply a function of them being a halogen design. The Depos put out as much light and have as much throw in the main beam as an HID, they simply don't have as much width. In comparison to the stock lamps, they have more width, but the falloff to the sides is faster so more noticeable.
On a scale of 1 to 10, using my 2006 BMW 530i with Bixenon lights (which also swivel in corners!!!) as a 10, the Depos rate about an 8, and the stock lamps about a 5. While the stock lamps were great when they came out, it is amazing how much lighting has moved forward in the past 20 years.
For back road driving, I add to side illumination by turning on my Hella 1000 lamps with corning lenses. These are no longer made, but were designed for use by rally drivers to provide better side illumination. They are between a fog and driving lamp, having the limited vertical distribution of a fog lamp, but slightly less width and greater throw (about the same throw as a standard low beam). I have included in my pictures below photos with and without these lit up supplementing the low beams.
High Beams:
This is important. When the Depos are properly wired to switch the H4 element turning on the high beams changes the pattern. The high beams focus further down the road and provide a more diffuse side illumination that extends much further than the low beam. This is important because it decreases foreground light (which causes your pupils to dilate) and allows you to focus further down the road. When combined with the H1 driving lamps built in, they have incredible throw, actually a fair bit better than the stock lamps which are still good in this regard.
In comparison to a bixenon HID, the Depo's are different. On the plus side, the outthrow the HID's. On the other side, because of the driving lamp element, they do have a hot spot from their focused long throw. This will happen no matter what driving lamp you have, it is simply a product of getting a long throw.
Overall:
The depo's are a worthwhile upgrade. To do them properly with bulbs and a wiring harness the upgrade runs about $450. If you want more light, the Depos form a great base for performing an HID retrofit with bixenon projectors. The HID retrofit would provide better side illumination and combined with the standard driving element a wonderful high beam with lots of broad distribution and throw. I am not doing the HIDs because of cost. Good HID projectors, ballasts, bulbs etc., are $300-500 and if you don't want to mod the Depos yourself, you are looking at another $300-600 to have it done properly.
Now to the beamshots (please excuse the grain, my DSLR is having some issues so these were shot with a point and shoot, with the exception of the wall shots, all were shot at 1/8 second, F3.3 and 24mm equivalent lens):
The first two are the low and high beam on a wall. Please ignore the slight tilt down to the right, that is my driveway not the lamps. On the low beams, notice the clean cutoff (not projector razor sharp, but sharp) and the kickup on the right for sign illumination. Also note the uniform distribution under the cutoff with no hotspots. On the high beams note the smooth hotspot with smooth falloff and nice side illumination with no hotspots.
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