check out the PIAA line of replacement bulbs, their ultrawhite and special coatings on their bulb are unreal. 160watts is the max i do believe... for both their h3 and h4 but there is NO comparison to a standad h3 / h4 of the same wattage. The PIAA's (about $100 - 200 for a set of bulbs) are the best you cna buy. Pure white light, makes regular bulbs look like dull orange light with a dead battery...