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Home Up Headlamp Conversion Terms




These specifications are presented in good faith researching information from various sources.   However, no guarantee or warranty is given to the accuracy of the above information.   You are advised to verify the correctness of these specifications prior to using them.  Use of these specifications assumes agreement with the disclaimer below. They are provided as a convenience to fellow enthusiasts and the author makes no expressed warranty to their accuracy, use at your own risk.

Below are definitions and explainations of terminology I use.  

Links are also provided to Competition Limited.  While there are many places to order auxiliary lighting supplies and parts, Gene Henderson the proprietor, has been a national competitor in SCCA Rally, Pro-Rally, and antique rally for many years.  I know Gene personally from the National Rally Circuit, and have always received quality parts and good service from him.  I shop there, you go where you are most comfortable to purchase stuff from.

  • The Power Formula -  A mathematical formula which defines the relationship of Voltage, Current, and Wattage.  While this formula may seem to be theoretical and bothersome, it is used to determine wire size and fuse size which will keep the electrical fires, and destruction of your fine machinery to a minimum.  Only modest math is required.  The basic formula is P= IE where P is power in Watts, E is electromotive force in Volts (should be 6 or 12 depending on your cars battery usually abbreviated 12VDC for 12 volts DC), and I is the current in Amperes.  Transposing we get I = P E.  Normal headlights are 55 Watts low beam, 65 Watts high beam, so your normal automotive fuse for headlights is  65W 12V =  5.4 Amps.  Check your fuses and you will generally see either a 7.5 Amp or 10 Amp fuse.  The wire diameter will also be rated for 10 Amps usually 18 AWG you can verify wire sizes vs amps here

  • Quartz Halogen / Quartz Iodine/QI lighting - Iodine is a Halogen gas, so the terms are synonymous.  In order to produce a brighter light, the tungsten filament is fed a much higher current (amperes) so it burns much brighter.  In order to keep the tungsten filament from boiling off and weakening itself, the bulb is pressurized with iodine gas which forces the tungsten molecules back on the filament.  The envelope of the bulb gets very hot because of the heat generated by the higher output filament.  In order to keep it from melting or cracking quartz glass is used.  When handling these bulbs, do not touch the glass surface, as the natural oils in your fingers will leave a residue which will turn black due to the high heat ruining the effectiveness of the lamp.  I usually use a clean paper towel to hold the lamp.  If you should touch the lamp, it can be cleaned using a clean cloth or paper towel, and isopropyl alcohol and then wiped dry.  QI Lamps are available in dual and single filament bulbs, and in many wattages and colors.

  • Xenon Gas Discharge - These lamps contain a pair of electrodes and are filled with Xenon Gas.  A High voltage is applied to the electrodes, and the gas is ionized into a plasma, which throws off a very bright blue white light.  These are the lights you see on many upscale cars such as Audi, Mercedes, etc.  An auxiliary kit is available to convert your standard headlights for about $600.  However, you must have separate high and low beam headlights as they are not available in dual filament varieties 

  • Auxiliary Wiring Harness -  a set of heavy duty wires, and relays that replace your existing headlight wiring that will handle the increased current of higher wattage lighting.  These are available at a reasonable cost and should be used if you increase the wattage of you lighting, these are not required if you use 55W/65W bulbs.

Last modified: April 26, 2005

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