Lighting - Not often thought about in much detail until A) one goes out B) You decide to blast down some corners at night and realize you can't see far enough ahead, or C) It rains while you're driving at night.

The biggest misconception I hear about lights is : "I have 100w driving lights, so I have adequate lighting!". Let me say this: Not necessarily. It's like saying you have a 300hp car - there are other factors involved. 300hp is great, but if your car weighs 4500lbs, then it's not quite so impressive. Lighting is the same - the lens and reflector design also determine how effective all that power is. Another item : not all bulbs are created equal. There are 4 main types of Halogen bulbs : H1 (single element) H2 (single element) H3 (single element and the most common) and H4 (Dual element - meaning low and high beam). There's a modified Halogen that's has been on the market for a few years - a "Dichronic Halogen". This is a Halogen bulb with a Dichronic coating, which filters and reflects various light wavlength's. Halogens also use Bromide or Xenon, which also affect efficiency.

The H1 is generally the most efficient of these (per watt). Light output is measured in lumens (like horsepower on an engine). Just as two 3.0 liter engines can have different horsepower ratings, two 130w lights can have different lumen ratings. A more useful measure of light output is reflective range - the distance a light can illuminate a reflective object clearly. Another indicator of light performance is vertical and horizontal spread.

The reflector's job is to reflect light accurately to the lenses so they can do their job. The lens's job is to direct the light where it is most effective, which is determined by the intended use of the light. Some newer designs incorporate a special reflector where the reflector is also determining the beam pattern, leaving the lens clear instead of fluted.

"Fog" (sometimes called "cornering") lights are supposed to have a wide and low illumination pattern, along with short reflective range. Below is a table showing different reflective ranges for the same 55w bulb

Note both light above have the same 55w bulb, but drastically different results. If the manufacturer doesn't list these specs (and many of the cheaper ones DON'T), you can assume that the above numbers are pretty close to what you've got. Bosch, PIAA, and CATZ are some of the higher quality brands.

There are also different subtypes of "driving" and "fog" lights. Pencil beam (sometimes called spot) lights are for REAL long range - 130w bulbs in these types of lighting systems can produce reflective ranges of over 9000' (approaching 2 MILES). PIAA also makes several types of lights for unique applications, and Bosch makes excellent replacement kits for OEM (for RACING only . . . AHEM) and auxiliary lighting.

The trick with all these choices is to have adequate lighting for ALL driving situations and not blind oncoming traffic when using standard (low) beams. Also keep in mind that each 100w bulb (regardless of fog or driving) will draw approx. 7.5amps (assuming 13.3 volts). Stick 4 of these on your car (two driving, two fog), along with your standard 60w high beams, and you get 39 amps for just your lights - not counting marker, dash, etc. Turn on a defroster, radio, etc., and you're over 50amps! Early alternators only put out 35 or so amps (on a good night). Of course, you are lucky to have a clear road to use all that power for very long.

Once you have your lighting purchased, don't overlook the wiring. DO NOT just run power to an illuminated switch, ground the lights, and run the power from the switch to the lights. use a relay! This sends the power through the relay and all the switch does is control the relay. Also, use fuses for each pair of lights, and at LEAST 12 gauge wire for the high powered stuff. When I was young(er) I made the mistake of no relay, and one night driving the 50+ miles from the beach to home at 2am, I came to a point where I needed to dim my lights, and the switch had got so hot that when I pressed on the rocker switch, nothing - it melted into its bracket! OOPS!

Good lighting is a blessing - ESPECIALLY when it's raining and 30%+ of your light is being reflected UP instead of back at you.

ByTheWay : The formula to use for current draw Watts/Volts = Amps

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