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Old 10-03-2009, 10:36 AM   #16 (permalink)
RobertSmalls
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Quote:
Originally Posted by darcane View Post
However, in the grand scheme of things, it's almost irrelevant. Saving 20 watts x two lights is 40 watts. 745watts per hp, so you're saving a whopping .05hp by switching lights. I'd rather have the better lighting.
40W is miniscule; true. But HID lamps deliver more lumens per watt, so a 35W HID is as bright as a 55W halogen. Also remember that 40W is 0.05HP of pure electricity, which takes about 0.1HP at the alternator shaft. If you do an enormous amount of nighttime driving, or if legislation requires that you drive with the headlights on, you stand to save a few gallons of gas a year.
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