I believe the fuses are rated at 10 amps per bulb, so that means the electrical system should be able to handle anything less than 120 watts. Heat is another story, so you might melt stuff if you get bulbs that are too hot. I'm running a 9005 conversion (65 watts) now and used to have 80w blue ricer bulbs for a few months, both with no electrical or heat problems. The 9005 conversion is very much better, btw.