a) Might want to post this in the Lighting forum, not here.
b)First thing you should do is thoroughly clean all your ground connections, and your battery post connections. Then clean your headlight connections at the bulb. Might look in Bentley for any other headlight-related grounds in the circuit.
After that, consider installing relays to your lights...running off battery voltage, even your stock wattage bulbs will seem much whiter and brighter. Then you can look into higher-wattage bulbs as the relays will safely run them without added current draw on your factory wiring.
If you're running stock US DOT-spec lenses, the beam pattern is terrible. Consider upgrading to a pair of european lenses, which have a much better beam pattern and sharper cutoff. If you run high wattage bulbs in your stock DOT lenses you run the risk of irritating a lot of oncoming drivers because the light 'dazzle' is pretty bad with them, even when properly aimed.
Eventually, upgrade to euro lights, but for right now just get new stock bulbs. I had the same problem with dull lighting about 2 years ago got new 9004s at WAL-MART and big difference! Course the old bulbs were 13 years old too!
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