Gauging interest: Corner light DRL bulb modification
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From: Republic of Texas
Sorry guys, I've been out the past few days with a nasty cold. I did get the tooling needed to start the project. Depending on how I'm feeling in the morning, I may commence with the modification.
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From: Republic of Texas
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From: Republic of Texas
Preliminary testing results are in:
The prototype piece used for this test had a ribbed-lens per the customer's request. This skewed output slightly, but did so for all the bulbs tested.
Bulbs tested:
- Gen III switchback in standard bottom mount (control)
- 8 Watt Projector switchback in rear mount
- 25w Cree Amber in rear mount
It's clear the parabolic reflector was designed for a single-point light source of the 3157 filament. The question is not if the new setup could mimic this focal point, but if the power of the new bulbs being tested would be substantially brighter than the older style LED bulbs that can fit in the existing mount.
Initial test was performed with the camera looking head-on at the housing as if facing the car. Camera was About 12" away from the light. settings were the same for all tests:
First is the Gen III switchback. This is the most powerful LED bulb I had available that would fit the traditional mount. It was relatively bright. Taking advantage of the reflector optics nicely.
The 8w in DRL/Turn signal mode was VERY bright. The projector did not in any way use the reflector of the housing, but was bright enough by itself to not need to do so. The effect was interesting as looking head on there was a 1" dot of light in the housing. Definitely an aftermarket look:
The 8w in parking light mode can only be described as an axillary driving light.
The brightest amber bulb yet was the Cree 25w. In low power, it rivals the 3157 in DRL mode.
In high power it appears just as bright as the traditional 3157 bulb (this will be confirmed later today)
To create a more objective test, I aimed the light at a black ABS backboard. I used black to reduce the amount of reflected light back to the camera to help emphasize the difference in output from different bulbs. Here are the results:
Gen III in DRL/Signal mode doing it's best. The light is focused into a narrow window and there's not a great deal of it.
The Gen III did much better in parking light mode, but White LEDs are always brighter than their equivalent amber counterparts.
The 8w switchback shows significantly greater output in DRL/Signal mode with a much wider pattern spread:
In Parking mode, the 8w appears to have the same overall output as the Gen III bulb, but spread out more. (this will be verified later today)
The 25w Cree did an excellent Job all around. In low mode, it was brighter and emitted a wider pattern than the Gen III in DRL/signal mode.
In High power mode, the 25w Cree was the brightest Amber bulb I've yet seen in these housings.
I will update the test results later today with a side-by side comparison of the older 3157 radial LED bulb and Gen III switchback compared to the 8W switchback and Cree 25w bulb. (I need to get another 3157 socket for testing and a 3157 amber bulb for comparison as well.
The prototype piece used for this test had a ribbed-lens per the customer's request. This skewed output slightly, but did so for all the bulbs tested.
Bulbs tested:
- Gen III switchback in standard bottom mount (control)
- 8 Watt Projector switchback in rear mount
- 25w Cree Amber in rear mount
It's clear the parabolic reflector was designed for a single-point light source of the 3157 filament. The question is not if the new setup could mimic this focal point, but if the power of the new bulbs being tested would be substantially brighter than the older style LED bulbs that can fit in the existing mount.
Initial test was performed with the camera looking head-on at the housing as if facing the car. Camera was About 12" away from the light. settings were the same for all tests:
First is the Gen III switchback. This is the most powerful LED bulb I had available that would fit the traditional mount. It was relatively bright. Taking advantage of the reflector optics nicely.
The 8w in DRL/Turn signal mode was VERY bright. The projector did not in any way use the reflector of the housing, but was bright enough by itself to not need to do so. The effect was interesting as looking head on there was a 1" dot of light in the housing. Definitely an aftermarket look:
The 8w in parking light mode can only be described as an axillary driving light.
The brightest amber bulb yet was the Cree 25w. In low power, it rivals the 3157 in DRL mode.
In high power it appears just as bright as the traditional 3157 bulb (this will be confirmed later today)
To create a more objective test, I aimed the light at a black ABS backboard. I used black to reduce the amount of reflected light back to the camera to help emphasize the difference in output from different bulbs. Here are the results:
Gen III in DRL/Signal mode doing it's best. The light is focused into a narrow window and there's not a great deal of it.
The Gen III did much better in parking light mode, but White LEDs are always brighter than their equivalent amber counterparts.
The 8w switchback shows significantly greater output in DRL/Signal mode with a much wider pattern spread:
In Parking mode, the 8w appears to have the same overall output as the Gen III bulb, but spread out more. (this will be verified later today)
The 25w Cree did an excellent Job all around. In low mode, it was brighter and emitted a wider pattern than the Gen III in DRL/signal mode.
In High power mode, the 25w Cree was the brightest Amber bulb I've yet seen in these housings.
I will update the test results later today with a side-by side comparison of the older 3157 radial LED bulb and Gen III switchback compared to the 8W switchback and Cree 25w bulb. (I need to get another 3157 socket for testing and a 3157 amber bulb for comparison as well.
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Final testing:
Side-by side comparison with the modified housing vs the unmodified housing:
Bulbs tested:
18 tri-chip SMD Amber radial bulb (factory mount)
Gen III switchback LED 21 LED bi-color tri-chip (factory mount)
8w Projector switchback (Custom Rear mount)
25w Cree (Custom rear mount)
Test 1: 18 tri-chip vs. Cree 25w.
The 18 tri-chip is virtually identical to the slightly more powerful 26-LED version. At present, these are the most powerful plug-and-play bulbs that replicate the Amber for both low and high power. Until now, this is because no other bulb was small enough to fit.
Comparison output against the black ABS: (Cree on left)
Low Power:
High Power:
Head on comparison: (Cree on right)
Low power:
High power
Test 2: Gen III switchback vs 8w Switchback
The Gen III switchback is a powerful bulb that fits in the stock housing, but the 8w Projector switchback offers a little more punch in Signal mode.
Against the ABS: (8W on left)
Signal Mode:
Parking lights: (not much difference)
Head on comparison (8W on Right)
Signal light:
Parking light: (had to switch to a different setting to prevent overload)
The next update will be to photos showing the new twist lock portion of the mount to use the factory socket.
Side-by side comparison with the modified housing vs the unmodified housing:
Bulbs tested:
18 tri-chip SMD Amber radial bulb (factory mount)
Gen III switchback LED 21 LED bi-color tri-chip (factory mount)
8w Projector switchback (Custom Rear mount)
25w Cree (Custom rear mount)
Test 1: 18 tri-chip vs. Cree 25w.
The 18 tri-chip is virtually identical to the slightly more powerful 26-LED version. At present, these are the most powerful plug-and-play bulbs that replicate the Amber for both low and high power. Until now, this is because no other bulb was small enough to fit.
Comparison output against the black ABS: (Cree on left)
Low Power:
High Power:
Head on comparison: (Cree on right)
Low power:
High power
Test 2: Gen III switchback vs 8w Switchback
The Gen III switchback is a powerful bulb that fits in the stock housing, but the 8w Projector switchback offers a little more punch in Signal mode.
Against the ABS: (8W on left)
Signal Mode:
Parking lights: (not much difference)
Head on comparison (8W on Right)
Signal light:
Parking light: (had to switch to a different setting to prevent overload)
The next update will be to photos showing the new twist lock portion of the mount to use the factory socket.