On H4 bulbs, there are 3 prongs:
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if i remember correctly, the positive and negative wires connect to the prongs on the left and top. What is the one on the right for?

 

the top and (___ side?) are for power ... the H4 bulb has 2 filaments in it, one for high beam one for low beam.

the 3rd prong would be ground , so ..depending on high/low beam the high I think is the top, the low is the one side.. .the 3rd is ground.

Go read about H4 bulbs on http://www.piaa.com they have different wattage/color temp. for H4's in high/low mode.

 

thanks for the input.. the reason i'm asking is because the h4's just arent as bright as the 9006's when i had the USDM headlights. I was thinking if i could use the highbeam filament when i turned on my lights that it would improve light output, but then again, i'm thinking the power used to power the low beam filament might not be enough power to power the high beam.. follow what i'm saying? LOL

 

davis, you ricer. What up Davis, haha.

 

The power used by the bulb is determined by the bulb filament. Both main and dip connect to the same power source (ie battery/altrnator), so you could whatever you like in terms of having which filament (main or lowbeam) on at any time by swapping wires etc. I think the lights are connected to separate relays, so it is even easier to do -- just energise the main beam relay ( you can check which this is by listening carefully as someone else flashes your lights. The relay will click letting you know which is the main beam relay. I suspect that operating both filaments at once in the same headlight will generate too much heat and reduce the life of your bulbs.

 

if you bought JDM headlights that came with bulbs, they suck. go buy some good ones. mine sucked as well. also, it may be the fact that they are aligned differently so you get a different light pattern. my $.02

 

i bought catz...they call them mean greenz...well because everything on it is in japanese but they are bright as hell

 

I'm in line to get some piaa super extreme once my car's runnin and I check my Dads house 3hours north..

I had piaa extreme 9005 in my low beam (9006) and they're awesome, nice bright white light.

 

Actually i have philips blue vision bulbs in my headlights. They look pretty much stock which is fine because i've had my fair share of "ricer" bulbs and i'm through with those. I also aligned my lights so that i could get the most possible light output to the ground so its not that. I just need brighter bulbs i guess..