Look at how quickly the life of the lamp degrades. Assuming the lamp is rated for 1000hr@13.5v, raising voltage from 13.5 to 14 decreases bulb life from 500 hours to 280 hours. Candlepower would improve just 13% from 15,000 to 17,000.
Small price to pay - new $30 bulbs every 20 years rather than every 35 years assuming the bulbs are on 14 hours a year; unlikely in an E-Type!
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Do people not drive home in the dark?
Bulbs are cheap, no reason to prolong their live by a few hours…
I drive with my lights on all the time so others can see me better.
Tom
Everything is designed with cost in mind. They did not use relays because there was no need to. The systems worked fine. The componets were plenty robust for the use. What would one say the design life of a 1960s car was? Fifty years later many are still working fine.
Tom
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In period reviews of the first E-Type’s universally complained about the seats, the gearbox and the lights. Jaguar addressed the complaints with new seats, new gearbox and new bonnet allowing deeper headlamp units. Reviewers blamed the poor lights on the cowled headlamps so Jaguar took them off.
My RHD 1962 FHC has NOS PL700 headlamps with 416 bulbs (60/36W) and I have only driven it once in the dark, through our village at 30mph, and it was terrifying. At 150mph Norman was a complete hero!
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I do that too. I’ve got to add a third brake light too.
Correct. That’s the part most people miss. It’s not linear. That 13% increase in output comes with a steep price.
Many years ago, in commercial buildings, we’d specify dimmers with limiters built into them. The limiter would not allow the voltage to go above a preset limit, say 95%. No one ever noticed they weren’t getting 100% of the light output but the maintenance folks loved it. Lamps changes were substantially reduced.
Well, as in all conversations on here, I’m learning a whole bunch!
Bottom line for me is, I think it’s a bit of a red herring to worry about changing headlights on these cars, because they might wear out a little bit more quickly, given that probably very few get that many “miles” on their filaments. Increased light output on a car, especially on an E type with the covered headlights, is well worth that extra cost, in my mind.
Sounds to me that there is more of an agreement that more volts at the headlamps gives more light( but less bulb life)…so replaceing original thin wire with thicker wire and relays gives less volt drop…so more light…as in Heuer (David,s) befor/after photos posted above…Steve
And IIRC, when Jaguar changed the headlight configuration to exposed headlights the complaints went away.
With switches, connectors and wires in good shape, what does adding relays do? You’ve reduced the amount of wire by a few feet. There just isn’t much to be gained.
The best upgrade is new LED lamps.
BTW, it’s easy enough to figure out what it might buy you by simply calculating the voltage drop with bigger wires, shorter wires, etc.
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Is there room for an LED conversion in the series 1 flat back headlight bowls? I was under the impression that they were too bulky.
Not that I know of. About the only after market headlamp reflectors that will fit are the Wipac ones. Cibie will not fit so getting the LED heat sink into the S1 bowls is a challenge.
Cibie and Wipac:
I have heard that Better Car Lighting have a kit to fit the S1 but no personal experience: Quicksilver Automotive - H4 Classic Car LED headlight upgrade kit
So jaguar did not improve the lighting by adding relays, they improved lighting by discarding the covers and moving the lights forward. So one of the best E type upgrades everyone should do is not relays, etc., but discard the ugly glass covers and go the preferred open setup.
Glad we have that settled.
Tom
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Sorry for not being clear. I meant that, with a small increase in voltage/power, the increase in color temperature (proportion of bulb output that is light, not heat) was about as significant as the increase in overall bulb output due to power increase. Thus the effect of voltage increase is about twice what you would expect if power only is considered.
Yes, bulb life diminishes, especially when rated voltage is exceeded. But without relays the voltage is often below the rated voltage, so adding a relay might not shorten life too much.
It’s interesting to note that, for ordinary tungsten bulbs, one must limit voltage to well below the optimum for more light without decreased filament life, which results in their characteristic yellowish color. That’s because the limiting factor is evaporation of metal from the filament, making the envelope appear black. One solution was to make the envelope very large, so that it could store more evaporated tungsten without turning as black. But the best solution was introduction of halogens under pressure–these prevented the envelope coating altogether. But to maintain the pressure and chemical reactions, a small envelope volume is required. And a small envelope gets very hot, which required quartz glass. So quartz-halogen bulbs operate at higher color temperatures with about the same life as regular bulbs.
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Might be redundant, how can anyone miss an E-Type!
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You’ve confirmed one of my theories as a lay person. At home, I always dimmed our lights where possible, we like a more relaxed, warmer environment rather than harsh lighting. In my past home that I lived in for 22 years, I never changed a ceiling light that was on dimmers. I think it was also important that they turned on to the dimmed level and not full blast and then down. One might have noticed, bulbs generally burn out when you first turn them on.
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I have a projector with a economy switch that supposedly doubles the (halogen) bulb life. There is a small difference in brightness and against all expectations almost no difference in colour temperature. I don’t care about the little extra brightness!
Differences in color temperature are very hard to notice unless you’ve got two lamps side by side.