I've got one of those aluminum Vector 1.5 million CP spotlights. It's got what I think is a 100 watt H3 bulb. What is the brightest, whitest bulb I can find to put into this thing? I seem to remember that it has to have a bulb with a filament that is vertical, and not horizontal, is this true?
Either a horizontal or vertical (axial) filament will work. The H-fil just throws an oblong spot. The Vector bulbs seem to be pretty good. You can get a visibly "whiter" beam by using any of the blue coated bulbs. If you want to try it, get the cheapest you can find. It's not worth it to put a Silverstar or PIAA or Optilux in there.
I have a 120 (or 130) watt bulb that was made by PIA. I haven't been able to find it on their website, and it might be a pretty old bulb. A friend of mine got it for a reduced price at the place he takes his car.