do the USDM and JDM headlights have the same light output potential? Or does one have an advantage over the other? I know that wattages vary for both of them, but I was comparing the 9005/9006 bulbs from my old USDM headlights and they look larger than the H4/H1 headlights, which made me wonder: is there a noticeable difference between beam pattern. brightness and sharpness? Or does it not make any diff at all. JDM headlight users I would assume would know best. (I havent installed my JDM set yet)

 

JDM headlight beam patterns are suited for right hand drive vehicles...it will never equal a USDM headlight performance no matter what bulbs are in it.

Otherwise other than wattage what does the 'size' of the bulb matter? It's in the same reflector housing...

 

a set of silverstars or piaas provide the best light possible on the jdm lights the wattage is the same for the usdm to jdm the only difference is the angle of jdm headlights is at a different angle and light up the left side of the road more than the right but the lights and the headlight housings are both better than the usdm spec counterparts imo

 

silverstars suck compared to PIAA xtremewhite plus, silverstars are much lower on the kelvan scale. stick with PIAAs.