That U.S.-spec Corrados were born with lousy illumination is well known. I'd lived with it every night since Project Corrado found its way to my garage, albeit at a rather dangerous price. Given the higher performance direction my Corrado was taking, it was time for a change. I was seriously overdriving the car at night, the stock headlamps little more than flashlights peering into the blackness.
There are several reasons why stock Corrado lights are deficient. First, U.S. regulations restricted the Euro-spec H4s; second, the VW sits fairly low to the ground, which makes the lenses prone to abrasion, thus degrading their clarity. After a few years of hard use, most Corrados got cataracts.
The hot ticket was upgrading to the Euro-spec Corrado lights, which offered higher wattage bulbs and a more focused beam. However, as the above picture shows, they still lack the punch of high-intensity-discharge lighting.
There are significant differences between HID lighting and conventional halogen-based systems. Basically, HID does not use the standard filament system of a regular bulb but works on a design where ballast is connected inline with the system that draws 35W and then reduces the current to increase voltage to 23,000 volts. It then creates an arc inside a xenon gas-filled HID bulb or capsule and excites the gas-producing light with a much higher lumens rating.
There are several misconceptions regarding upgraded lighting; the biggest is the kelvin scale. Some seem to think the hotter the bulb, the more light it produces. It ain't true. The kelvin scale is based on a theoretical block of black metal. As the block is heated, it begins to change color. In the first stages, the block begins to glow a dull red or orange-this is a warm light with a measurement of 2500 K to 3200 K. As the block continues to warm, the orange hue is replaced with green and blue, eventually becoming white with a temperature of 5600 K (the same color as the sun). Above 5600 K, the light becomes more blue and purplish. Ultimately, changing the bulb temperature only changes the quality of light, not the quantity.
The folks at The HID Factory have brilliant solutions for dim cars. The HID retrofit kit for the Corrado (and most VWs for that matter) has transformed my car into the ultimate nocturnal cruiser. The difference is simply staggering, like a candle compared to the sun. It's hard to believe I lived so long without them.
The HID Factory kit is comprised of two Euro-spec headlamps fitted with the original Philips 4100 K bulbs found in many of today's luxury vehicles. These are not re-based bulbs-they have a ring machined to fit in place of a halogen bulb in the same housing. They use the D2-type connector (except for the smaller H1 type) for the best possible connection and reliability. The ballast units are from Philips GmbH and feature sealed snap fit plugs for good connections.
The HID Factory system is pretty much a plug-and-play program using the factory's tri-plug connector and stock mounting points. Because of the initial increase of amperage during start-up, it is necessary to change the 10-amp headlamp fuses to 20 amps (I discovered this after burning through a bag of fuses).
Due to deadline constraints, I was unable to hook up the high beams and city lights. We also noticed the high-beam indicator is always on. I can't imagine what the brights would look like, as the standard low beams are better than most systems' high beams. The supplied relay kit will most likely remedy these things.
The HID Factory lighting system ain't cheap. It is, however, the best aftermarket lighting I have ever seen.